Definition of the
CIDOC
Conceptual Reference Model

 

 

 

 

 

 

Produced by the ICOM/CIDOC

Documentation Standards Group,

continued by the

CIDOC CRM Special Interest Group

 

 

 

Version 5.0.2

 

January 2010

 

 

 

 

Editors: Nick Crofts, Martin Doerr, Tony Gill, Stephen Stead, Matthew Stiff.

 

 

Copyright © 2003 ICOM/CIDOC CRM Special Interest Group
Table of Contents

 

 

 

Introduction               i

Objectives of the CIDOC CRM               i

Scope of the CIDOC CRM               i

Compatibility with the CRM               ii

Utility of CRM compatibility               ii

The Information Integration Environment               iii

CRM-Compatible Form               iv

CRM Compatibility of Data Structure               v

CRM Compatibility of Information Systems               vi

Compatibility claim declaration               vii

Applied Form               viii

Terminology               viii

Property Quantifiers               xiii

Naming Conventions               xv

Modelling principles               xv

Monotonicity               xv

Minimality               xvi

Shortcuts               xvi

Disjointness               xvi

About Types               xvi

Extensions               xviii

Coverage               xviii

Examples               xix

Class & Property Hierarchies               xx

CIDOC CRM Class Hierarchy               xxii

CIDOC CRM Property Hierarchy:               xxv

CIDOC CRM Class Declarations               1

E1 CRM Entity               2

E2 Temporal Entity               2

E3 Condition State               3

E4 Period               3

E5 Event               4

E6 Destruction               4

E7 Activity               5

E8 Acquisition               5

E9 Move               6

E10 Transfer of Custody               6

E11 Modification               7

E12 Production               7

E13 Attribute Assignment               8

E14 Condition Assessment               8

E15 Identifier Assignment               9

E16 Measurement               9

E17 Type Assignment               10

E18 Physical Thing               10

E19 Physical Object               10

E20 Biological Object               11

E21 Person               11

E22 Man-Made Object               12

E24 Physical Man-Made Thing               12

E25 Man-Made Feature               12

E26 Physical Feature               12

E27 Site               13

E28 Conceptual Object               13

E29 Design or Procedure               14

E30 Right               14

E31 Document               14

E32 Authority Document               15

E33 Linguistic Object               15

E34 Inscription               15

E35 Title               16

E36 Visual Item               16

E37 Mark               17

E38 Image               17

E39 Actor               17

E40 Legal Body               18

E41 Appellation               18

E42 Identifier               19

E44 Place Appellation               19

E45 Address               19

E46 Section Definition               20

E47 Spatial Coordinates               20

E48 Place Name               20

E49 Time Appellation               20

E50 Date               21

E51 Contact Point               21

E52 Time-Span               21

E53 Place               22

E54 Dimension               22

E55 Type               23

E56 Language               23

E57 Material               24

E58 Measurement Unit               24

E59 Primitive Value               24

E60 Number               25

E61 Time Primitive               25

E62 String               25

E63 Beginning of Existence               26

E64 End of Existence               26

E65 Creation               26

E66 Formation               26

E67 Birth               27

E68 Dissolution               27

E69 Death               27

E70 Thing               28

E71 Man-Made Thing               28

E72 Legal Object               28

E73 Information Object               29

E74 Group               29

E75 Conceptual Object Appellation               30

E77 Persistent Item               30

E78 Collection               30

E79 Part Addition               31

E80 Part Removal               31

E81 Transformation               32

E82 Actor Appellation               32

E83 Type Creation               32

E84 Information Carrier               33

E85 Joining               33

E86 Leaving               33

E87 Curation Activity               34

E89 Propositional Object               34

E90 Symbolic Object               35

CIDOC CRM Property Declarations               36

P1 is identified by (identifies)               37

P2 has type (is type of)               37

P3 has note               37

P4 has time-span (is time-span of)               38

P5 consists of (forms part of)               38

P7 took place at (witnessed)               38

P8 took place on or within (witnessed)               39

P9 consists of (forms part of)               39

P10 falls within (contains)               39

P11 had participant (participated in)               40

P12 occurred in the presence of (was present at)               40

P13 destroyed (was destroyed by)               40

P14 carried out by (performed)               41

P15 was influenced by (influenced)               41

P16 used specific object (was used for)               41

P17 was motivated by (motivated)               42

P19 was intended use of (was made for):               42

P20 had specific purpose (was purpose of)               42

P21 had general purpose (was purpose of)               43

P22 transferred title to (acquired title through)               43

P23 transferred title from (surrendered title through)               43

P24 transferred title of (changed ownership through)               44

P25 moved (moved by)               44

P26 moved to (was destination of)               44

P27 moved from (was origin of)               44

P28 custody surrendered by (surrendered custody through)               45

P29 custody received by (received custody through)               45

P30 transferred custody of (custody transferred through)               45

P31 has modified (was modified by)               45

P32 used general technique (was technique of)               46

P33 used specific technique (was used by)               46

P34 concerned (was assessed by)               46

P35 has identified (was identified by)               47

P37 assigned (was assigned by)               47

P38 deassigned (was deassigned by)               47

P39 measured (was measured by):               47

P40 observed dimension (was observed in)               48

P41 classified (was classified by)               48

P42 assigned (was assigned by)               48

P43 has dimension (is dimension of)               48

P44 has condition (is condition of)               49

P45 consists of (is incorporated in)               49

P46 is composed of (forms part of)               49

P48 has preferred identifier (is preferred identifier of)               50

P49 has former or current keeper (is former or current keeper of)               50

P50 has current keeper (is current keeper of)               50

P51 has former or current owner (is former or current owner of)               51

P52 has current owner (is current owner of)               51

P53 has former or current location (is former or current location of)               51

P54 has current permanent location (is current permanent location of)               52

P55 has current location (currently holds)               52

P56 bears feature (is found on):               52

P57 has number of parts               53

P58 has section definition (defines section)               53

P59 has section (is located on or within)               53

P62 depicts (is depicted by)               54

P65 shows visual item (is shown by)               54

P67 refers to (is referred to by)               55

P68 foresees use of (use foreseen by):               55

P69 is associated with               55

P70 documents (is documented in)               55

P71 lists (is listed in)               56

P72 has language (is language of)               56

P73 has translation (is translation of)               56

P74 has current or former residence (is current or former residence of)               56

P75 possesses (is possessed by)               57

P76 has contact point (provides access to)               57

P78 is identified by (identifies)               57

P79 beginning is qualified by               57

P80 end is qualified by               57

P81 ongoing throughout               58

P82 at some time within               58

P83 had at least duration (was minimum duration of)               58

P84 had at most duration (was maximum duration of)               58

P86 falls within (contains)               59

P87 is identified by (identifies)               59

P88 consists of (forms part of)               59

P89 falls within (contains)               59

P90 has value               60

P91 has unit (is unit of)               60

P92 brought into existence (was brought into existence by)               60

P93 took out of existence (was taken out of existence by)               60

P94 has created (was created by)               61

P95 has formed (was formed by)               61

P96 by mother (gave birth)               61

P97 from father (was father for)               61

P98 brought into life (was born)               62

P99 dissolved (was dissolved by)               62

P100 was death of (died in)               62

P101 had as general use (was use of)               63

P102 has title (is title of)               63

P103 was intended for (was intention of)               63

P104 is subject to (applies to)               63

P105 right held by (has right on)               64

P106 is composed of (forms part of)               64

P107 has current or former member (is current or former member of)               64

P108 has produced (was produced by)               65

P109 has current or former curator (is current or former curator of)               65

P110 augmented (was augmented by)               65

P111 added (was added by)               65

P112 diminished (was diminished by)               66

P113 removed (was removed by)               66

P114 is equal in time to               66

P115 finishes (is finished by)               66

P116 starts (is started by)               67

P117 occurs during (includes)               67

P118 overlaps in time with (is overlapped in time by)               67

P119 meets in time with (is met in time by)               67

P120 occurs before (occurs after)               68

P121 overlaps with               68

P122 borders with               68

P123 resulted in (resulted from)               68

P124 transformed (was transformed by)               69

P125 used object of type (was type of object used in)               69

P126 employed (was employed in)               69

P127 has broader term (has narrower term)               70

P128 carries (is carried by)               70

P129 is about (is subject of)               70

P130 shows features of (features are also found on)               70

P131 is identified by (identifies)               71

P132 overlaps with               71

P133 is separated from               71

P134 continued (was continued by)               71

P135 created type (was created by)               72

P136 was based on (supported type creation)               72

P137 exemplifies ( is exemplified by )               72

P138 represents (has representation)               72

P139 has alternative form               73

P140 assigned attribute to (was attributed by)               73

P141 assigned (was assigned by)               73

P142 used constituent (was used in)               74

P143 joined (was joined by)               74

P144 joined with (gained member by)               74

P145 separated (left by)               75

P146 separated from (lost member by)               75

P147 curated (was curated by)               76

P148 has component (is component of)               76

References:               77

APPENDIX               78

Editorial notes               78

Amendments to version 3.3               79

Amendments to version 3.3.1               80

Amendments to version 3.3.2               81

Amendments to version 3.4               85

Amendments to version 3.4.1               88

Amendments to version 3.4.2               88

Amendments to version 3.4.9               89

Amendments to version 4.2               89

Amendments to version 4.2.1               90

P16 used specific object (was used for)               91

P32 used general technique (was technique of)               91

P33 used specific technique (was used by)               91

P35 has identified (identified by)               91

Amendments to version 4.2.2               91

E1 CRM Entity               91

E3 Condition State               91

E4 Period               91

E15 Identifier Assignment               92

E29 Design or Procedure               93

E33 Linguistic Object               93

E41 Appellation               93

E42 Identifier               93

E51 Contact Point               94

E54 Dimension               94

E74 Group               94

E85, E80 have been added               95

E85 Joining               95

E80 Leaving               96

P3 has note               96

P36               96

P37 assigned (was assigned by)               97

P38 deassigned (was deassigned by )               97

P47 is identified by(identifies)               97

P48 has preferred identifier (is preferred identifier of               97

P69 is associated with               98

P139 has alternative form               98

P142, P143, P144, P145, P146, P148               99

P142 used constituent (was used in)               99

P143 joined (was joined by)               99

P144 joined with (gained member by)               99

P145 separated (left by)               100

P146 separated from (lost member by)               100

P148 is identified by (identifies)               100

Amendments to version 4.2.4               101

Delete the word “domain”               101

E15               101

E42               101

E85 and E86               101

Amendments to version 4.2.5               103

Changes in the terminology               103

E89, E90 have been added:               104

E89 Propositional Object               104

E90 Symbolic Object               104

P148  has been changed               105

P67, P129 changed domain               106

P106 changed domain and range               106

Changes in the scope note of E7 Activity P16               106

P16 used specific object (was used for)               107

Changes to E54               107

Changes to the text of E28               108

E28 Conceptual Object               109

E28 Conceptual Object               109

Changes in the domain, range and superproperty of P137               110

P137 is exemplified by (exemplifies) (old)               110

P137 exemplifies (is exemplified by) (NEW)               110

P39               110

P39 measured (was measured by):               110

P39 measured (was measured by):               111

Amendments to version 4.2.5a               111

The range and the scope note of P20 has been changed               111

P20 had specific purpose (was purpose of)               111

The scope note of P21 has been changed and an example is added               112

P21 had general purpose (was purpose of)               112

P105 has been superproperty of P52               112

The scope note of P105 has been changed               112

P105 right held by (has right on)               112

Proofreading:               112

Amendments to version 4.3               113

P68 usually employs (is usually employed by)               113

Compatibility               114

About Types               121

E55 Type               123

E66 Formation               123

P143 joined was joined by)               124

P144 joined with (gained member by)               124

P5 consists of               124

E78 Collection               125

E87 Curation Activity               125

P147 curated (was curated by)               125

P109 has current or former curator (is current or former curator of)               126

Amendments to version 5.0               126

Compatibility claim declaration               126

E78 Collection               126

P107 has current or former member (is current or former member of)               126

P144 joined with (gained member by)               127

Proofreading:               127

Amendments to version 5.01               128

Proofreading:               128

Amendments to version 5.02               129

E5 Event, E6 Destruction               129

E12 Production               129

E29 Design or Procedure               129

E35 Title               129

E70 Thing               129

E75 Conceptual Object Appellation               130

E81 Transformation – issue 165               130

P4 has time-span (is time-span of)               131

P5 consists of (forms part of)               131

P14 carried out by (performed) – issue 170               131

P44 has condition (is condition of) – issue 144               131

P62 depicts (is depicted by)               131

P65 shows visual item (is shown by) – issue 169               131

P107 has current or former member (is current or former member of)               131

P148 has component (is component of)               132

Proofreading:               132


Definition of the CIDOC Conceptual Reference Model

Introduction

 

This document is the formal definition of the CIDOC Conceptual Reference Model (“CRM”), a formal ontology intended to facilitate the integration, mediation and interchange of heterogeneous cultural heritage information. The CRM is the culmination of more than a decade of standards development work by the International Committee for Documentation (CIDOC) of the International Council of Museums (ICOM). Work on the CRM itself began in 1996 under the auspices of the ICOM-CIDOC Documentation Standards Working Group. Since 2000, development of the CRM has been officially delegated by ICOM-CIDOC to the CIDOC CRM Special Interest Group, which collaborates with the ISO working group ISO/TC46/SC4/WG9 to bring the CRM to the form and status of an International Standard.

Objectives of the CIDOC CRM

The primary role of the CRM is to enable information exchange and integration between heterogeneous sources of cultural heritage information. It aims at providing the semantic definitions and clarifications needed to transform disparate, localised information sources into a coherent global resource, be it within a larger institution, in intranets or on the Internet.

Its perspective is supra-institutional and abstracted from any specific local context. This goal determines the constructs and level of detail of the CRM.

 

More specifically, it defines and is restricted to the underlying semantics of database schemata and document structures used in cultural heritage and museum documentation in terms of a formal ontology. It does not define any of the terminology appearing typically as data in the respective data structures; however it foresees the characteristic relationships for its use. It does not aim at proposing what cultural institutions should document. Rather it explains the logic of what they actually currently document, and thereby enables semantic interoperability.

 

It intends to provide an optimal analysis of the intellectual structure of cultural documentation in logical terms. As such, it is not optimised to implementation-specific storage and processing aspects. Rather, it provides the means to understand the effects of such optimisations to the semantic accessibility of the respective contents.

 

The CRM aims to support the following specific functionalities:

·         Inform developers of information systems as a guide to good practice in conceptual modelling, in order to effectively structure and relate information assets of cultural documentation.

·         Serve as a common language for domain experts and IT developers to formulate requirements and to agree on system functionalities with respect to the correct handling of cultural contents.

·         To serve as a formal language for the identification of common information contents in different data formats; in particular to support the implementation of automatic data transformation algorithms from local to global data structures without loss of meaning. The latter being useful for data exchange, data migration from legacy systems, data information integration and mediation of heterogeneous sources.

·         To support associative queries against integrated resources by providing a global model of the basic classes and their associations to formulate such queries.

·         It is further believed, that advanced natural language algorithms and case-specific heuristics can take significant advantage of the CRM to resolve free text information into a formal logical form, if that is regarded beneficial. The CRM is however not thought to be a means to replace scholarly text, rich in meaning, by logical forms, but only a means to identify related data.

 

Users of the CRM should be aware that the definition of data entry systems requires support of community-specific terminology, guidance to what should be documented and in which sequence, and application-specific consistency controls. The CRM does not provide such notions.

 

By its very structure and formalism, the CRM is extensible and users are encouraged to create extensions for the needs of more specialized communities and applications.

Scope of the CIDOC CRM

The overall scope of the CIDOC CRM can be summarised in simple terms as the curated knowledge of museums.

 

However, a more detailed and useful definition can be articulated by defining both the Intended Scope, a broad and maximally-inclusive definition of general application principles, and the Practical Scope, which is expressed by the overall scope of a reference set of specific identifiable museum documentation standards and practices that the CRM aims to encompass, however restricted in its details to the limitations of the Intended Scope.

 

The Intended Scope of the CRM may be defined as all information required for the exchange and integration of heterogeneous scientific documentation of museum collections. This definition requires further elaboration:

 

·         The term “scientific documentation” is intended to convey the requirement that the depth and quality of descriptive information that can be handled by the CRM should be sufficient for serious academic research. This does not mean that information intended for presentation to members of the general public is excluded, but rather that the CRM is intended to provide the level of detail and precision expected and required by museum professionals and researchers in the field.

·         The term “museum collections” is intended to cover all types of material collected and displayed by museums and related institutions, as defined by ICOM [1] . This includes collections, sites and monuments relating to fields such as social history, ethnography, archaeology, fine and applied arts, natural history, history of sciences and technology.

·         The documentation of collections includes the detailed description of individual items within collections, groups of items and collections as a whole. The CRM is specifically intended to cover contextual information: the historical, geographical and theoretical background that gives museum collections much of their cultural significance and value.

·         The exchange of relevant information with libraries and archives, and the harmonisation of the CRM with their models, falls within the Intended Scope of the CRM.

·         Information required solely for the administration and management of cultural institutions, such as information relating to personnel, accounting, and visitor statistics, falls outside the Intended Scope of the CRM.

 

The Practical Scope [2] of the CRM is expressed in terms of the current reference standards for museum documentation that have been used to guide and validate the CRM’s development. The CRM covers the same domain of discourse as the union of these reference standards; this means that data correctly encoded according to these museum documentation standards there can be a CRM-compatible expression that conveys the same meaning.

 

Compatibility with the CRM

Utility of CRM compatibility

 

The goal of the CRM is to enable the integration of the largest number of information resources. Therefore it aims to provide the greatest flexibility of systems to become compatible, rather than imposing one particular solution.

 

Users intending to take advantage of the semantic interoperability offered by the CRM may want to make parts of their data structures compatible with the CRM. Compatibility may pertain either to the associations by which users would like their data to be accessible in an integrated environment, or to the contents intended for transport to other environments, allowing encoded meaning to be preserved in a target system.

 

The CRM does not require complete matching of all user documentation structures with the CRM, nor that systems should always implement all CRM concepts and associations; instead it leaves room both for extensions, needed to capture the full richness of cultural information, and for simplifications, required for reasons of economy.

 

Furthermore, the CRM provides a means of interpreting structured information so that large amounts of data can be transformed or mediated automatically. It does not require unstructured or semi-structured free text information to be analysed into a formal logical representation. In other words, it does not aim to provide more structure than users have previously provided. The interpretation of information in the form of free text falls outside the scope of compatibility considerations. The CRM does, however, allow free text information to be integrated with structured information.

The Information Integration Environment

 

The notion of CRM compatibility is based on interoperability . Interoperability is best defined on the basis of specific communication practices between information systems . Following current practice, we distinguish the following types of information integration environments pertaining to information systems:

 

1.       Local information systems . These are either collection management systems or content management systems that constitute institutional memories and are maintained by an institution. They are used for primary data entry, i.e. a relevant part of the information, be it data or metadata, is primary information in digital form that fulfils institutional needs.

 

2.       Integrated access systems . These provide an homogeneous access layer to multiple local systems.  The information they manage resides primarily on local systems. We distinguish between:

a.       Materialized access systems , which physically import data provided by local systems, using a data warehouse approach. Such systems may employ so-called metadata harvesting techniques or rely on data submission. Data may be transformed to respect the schema of the access system before being merged. 

b.       Mediation systems, [Gio Wiederholt] which send out queries, formulated according to a virtual global schema, to multiple local systems and then collect and integrate the answers. The queries may be transformed to a local schema either by the mediation system or by the receiving local system itself.

`              

Local systems may also import data from other systems, in order to complement collections, or to merge information from other systems. An information system may export information for migration and preservation.

 

Compatibility with the CRM pertains to one or more of the following data communication capabilities or use cases :

1.       data falling within the scope of the CRM can be exported from an information system into an encoded form without loss of meaning with respect to CRM concepts;

2.       data falling within the scope of the CRM can be transformed into another encoded form without loss of meaning with respect to CRM concepts;

3.       data falling within the scope of the CRM can be imported from an encoded form into an information system without loss of meaning with respect to CRM concepts;

4.       data falling within the scope of the CRM that is contained in an information system can be queried and retrieved exhaustively in terms of CRM concepts, subject to the expressive power of a particular query language.

 

Any declaration of CRM compatibility must specify one or more of the above use cases. System and data structure providers shall not declare their products as “CRM compatible” without specifying the appropriate use cases as detailed below.

 

In the context of this chapter, the expression “without loss of meaning with respect to the CRM concepts” means the following: The CRM concepts are used to classify items of discourse and their relationships. By virtue of this classification, data can be understood as propositions of a kind declared by the CRM about real world facts, such as “Object x. forms part of: Object y”. In case the encoding, i.e. the language used to describe a fact, is changed, only an expert conversant with both languages can assess if the two propositions do indeed describe the same fact. If this is the case, then there is no loss of meaning with respect to CRM concepts. Communities of practice requiring fewer concepts than the CRM declares may restrict CRM compatibility with respect to an explicitly declared subset of the CRM.

 

Users of this standard may communicate CRM compatible data, as detailed below, with data structures and systems that are either more detailed and specialized than the CRM or whose scope extends beyond  that of the CRM. In such cases, the standard guarantees only the preservation of meaning with respect to CRM concepts. However, additional information that can be regarded as extending CRM concepts may be communicated and preserved in CRM compatible systems through the appropriate use of controlled terminology. The specification of the latter techniques does not fall under the scope of this standard. Communities of practice requiring extensions to the CRM are encouraged to declare their extensions as CRM-compatible standards.

CRM-Compatible Form

The CRM is a formal ontology which can be expressed in terms of logic or a suitable knowledge representation language. Its concepts can be instantiated as sets of statements that provide a model of reality. We call any encoding of such CRM instances in a formal language that preserves the relations between the CRM classes , properties and inheritance rules   a “CRM-compatible form”. Hence data expressed in any CRM-compatible form can be automatically transformed into any other CRM-compatible form without loss of meaning. Classes and properties of the CRM are identified by their initial codes, such as “E55” or “P12”. The names of classes and properties of a CRM-compatible form may be translated into any local language, but the identifying codes must be preserved . A CRM-compatible form should not implement the quantifiers of CRM properties as cardinality constraints for the encoded instances. Quantifiers may be implemented in an informative way, or not at all. Statements that violate quantifiers should be treated as alternative knowledge .

 

Any encoding of CRM instances in a formal language that preserves the relations within a consistent subset of CRM classes , properties and inheritance rules is regarded a “reduced CRM-compatible form”, if:

·         all the conditions applicable to a CRM compatible form are respected;

·         the subset does not violate the rules of subsumption and inheritance;

·         any instance of the reduced CRM-compatible form is also a valid instance of a (full) CRM compatible form

·         the subset contains at least the following concepts:

 

E1

CRM Entity

E2

-

Temporal Entity

E4

-

-

Period

E5

-

-

-

Event

E7

-

-

-

-

Activity

E11

-

-

-

-

-

Modification

E12

-

-

-

-

-

-

Production

E13

-

-

-

-

-

Attribute Assignment

E65

-

-

-

-

-

Creation

E63

-

-

-

-

Beginning of Existence

E12

-

-

-

-

-

Production

E65

-

-

-

-

-

Creation

E64

-

-

-

-

End of Existence

E77

-

Persistent Item

E70

-

-

Thing

E72

-

-

-

Legal Object

E18

-

-

-

-

Physical Thing

E24

-

-

-

-

-

Physical Man-Made Thing

E90

-

-

-

-

Symbolic Object

E71

-

-

-

Man-Made Thing

E24

-

-

-

-

Physical Man-Made Thing

E28

-

-

-

-

Conceptual Object

E89

-

-

-

-

-

Propositional Object

E30

-

-

-

-

-

-

Right

E73

-

-

-

-

-

-

Information Object

E90

-

-

-

-

-

Symbolic Object

E41

-

-

-

-

-

-

Appellation

E73

-

-

-

-

-

-

Information Object

E55

-

-

-

-

-

Type

E39

-

-

Actor

E74

-

-

-

Group

E52

-

Time-Span

E53

-

Place

E54

-

Dimension

E59

Primitive Value

E61

-

Time Primitive

E62

-

String

 

Property id
Property Name

Entity – Domain

Entity - Range

P1

is identified by (identifies)

E1 CRM Entity

E41 Appellation

P2

has type (is type of)

E1 CRM Entity

E55 Type

P3

has note

E1 CRM Entity

E62 String

P4

has time-span (is time-span of)

E2 Temporal Entity

E52 Time-Span

P7

took place at (witnessed)

E4 Period

E53 Place  

P10

falls within (contains)

E4 Period

E4 Period

P12

occurred in the presence of (was present at)

E5 Event

E77 Persistent Item

P11

   -   had participant (participated in)

E5 Event

E39 Actor

P14

   -   -   carried out by (performed)

E7 Activity

E39 Actor

P16

   -   used specific object (was used for)

E7 Activity

E70 Thing

P31

   -   has modified (was modified by)

E11 Modification

E24 Physical Man-Made Thing

P108

   -  -    has produced (was produced by)

E12 Production

E24 Physical Man-Made Thing

P92

   -   brought into existence (was brought into existence by)

E63 Beginning of Existence

E77 Persistent Item

P108

   -  -    has produced (was produced by)

E12 Production

E24 Physical Man-Made Thing

P94

   -   -   has created (was created by)

E65 Creation

E28 Conceptual Object

P93

   -   took out of existence (was taken out of existence by)

E64 End of Existence

E77 Persistent Item

P15

was influenced by (influenced)

E7 Activity

E1 CRM Entity

P16

   -   used specific object (was used for)

E7 Activity

E70 Thing

P20

had specific purpose (was purpose of)

E7 Activity

E7 Activity

P43

has dimension (is   dimension   of)

E70 Thing

E54 Dimension

P46

is composed of (forms part of)

E18 Physical Thing

E18 Physical Thing

P59

has section (is located on or within)

E18 Physical Thing

E53 Place  

P67

refers to ( is referred to by)

E89 Propositional Object

E1 CRM Entity

P75

possesses (is possessed by)

E39 Actor

E30 Right

P81

ongoing throughout

E52 Time-Span

E61 Time Primitive

P82

at some time within

E52 Time-Span

E61 Time Primitive

P89

falls within (contains)

E53 Place  

E53 Place  

P104

is subject to (applies to)

E72 Legal Object

E30 Right

P106

is composed of (forms part of)

E90 Symbolic Object

E90 Symbolic Object

P107

has current or former member (is current or former member of)

E74 Group

E39 Actor

P127

has broader term (has narrower term)

E55 Type

E55 Type

P128

carries (is carried by)

E24 Physical Man-Made Thing

E73 Information Object

P130

shows features of (features are also found on)

E70 Thing

E70 Thing

P140

assigned attribute to (was attributed by)

E13 Attribute Assignment

E1 CRM Entity

P141

assigned (was assigned by)

E13 Attribute Assignement

E1 CRM Entity

P148

has component (is component of)

E89 Propositional Object

E89 Propositional Object

 

CRM Compatibility of Data Structure

 

A data structure is export-compatible with the CRM if it is possible to transform any data from this data structure into a CRM-compatible form without loss of meaning . Implicit concepts may be present in elements of the data structure that are not supported by the CRM. As long as these concepts can be encoded as instances of E55 Type (i.e. as terminology) and attached unambiguously to their respective data items with suitable properties, the data structure is still regarded as export compatible.

 

Note that not all CRM concepts may be represented by elements of an export-compatible data structure. All data from export-compatible data structures can be transported in a CRM-compatible form. In particular any CRM compatible form or reduced CRM-compatible form is export-compatible with the CRM.

 

A data structure is import-compatible with the CRM if it is possible to automatically transform any data from a CRM-compatible form into this data structure without loss of meaning , simply on the basis of knowledge about the data structure elements being used . This implies that a data record transformed into this data structure from a CRM-compatible form can be transformed back into the CRM-compatible form without loss of meaning . Note that the back-transformation into a CRM-compatible form may result in a data record that is semantically equivalent but not identical with the original.

 

Any CRM-compatible form is automatically import-compatible with the CRM. Note that an import-compatible data structure may be semantically richer than the CRM. It may contain elements that, through the use of a transformation algorithm, can be made to correspond to CRM concepts or specializations thereof or that contain elements with meanings that fall outside the scope of the CRM. However, it must not contain elements that overlap in meaning with CRM concepts and which cannot be subsumed via transformation by a CRM concept other than E1 CRM Entity and E77 Persistent Item. 

 

Import-compatible data structures may be used to transport data for applications that require concepts that lie beyond the scope of the CRM, as well as data from any export-compatible data structure. Note that, in general, applications may make use of data from a CRM import-compatible data structure that has been exported into a CRM compatible form by semantic reduction to CRM concepts, i.e. by generalizing all subsumed concepts to the most specific CRM concept applicable, and by discarding elements that fall outside the scope of the CRM.

 

A data structure is partially import - compatible with the CRM if the above holds for a reduced CRM-compatible form.

 

CRM Compatibility of Information Systems

 

An information system is export-compatible with the CRM if it is possible to export all user data from this information system into an import-compatible data structure. This capability is the recommended kind of CRM-compatibility for local information systems.

 

An information system is partially export compatible if it is possible to export all user data from this information system into a partially import-compatible data structure. This is not the recommended kind of CRM-compatibility, but it may not be feasible for legacy systems to acquire a higher level of CRM compatibility without unreasonable effort. This reduced level of CRM compatibility is nonetheless highly useful.

 

Note that there is no minimum requirement for the classes and properties that must be present in the exported user data. Therefore it is possible that the data may pertain to instances of just a single property, such as E21 Person. P131 is identified by : E82 Actor Appellation.

 

An information system is import-compatible with the CRM if it is possible to import data encoded in a CRM-compatible form and to access the data in a manner equivalent to and homogeneous with all generic data of this system that fall under the same concepts. This capability is considered as the normal kind of CRM compatibility for integrated access systems that physically copy source data in a data warehouse style (materialized access systems).

 

An information system is partially import-compatible with the CRM if it is possible to import data encoded in a reduced CRM-compatible form and to access the data in a manner equivalent to and homogeneous with all generic data of this system that fall under the same concepts. Depending on the functional requirements, it makes sense for integrated access systems to offer access services of reduced complexity by being only partially import-compatible with the CRM.

 

Note that it makes sense for integrated access systems to import data from extended data structures by semantic reduction to CRM defined concepts.

 

Note that local information system providers may choose to make their systems import-compatible with the CRM in order to exchange data, for example in the case of museum object loans or for system migration purposes. Communities of practice may choose to agree on import compatibility for extended data structures.

 

Some local information systems are likely to focus on specialized subject areas, such as inscriptions. For these specialized systems, the ability to import a specific data structure is recommended. This should be export-compatible with the CRM, and encompass the concepts that are required by the subject matter (“dedicated import compatibility”).

 

An information system is access-compatible with the CRM if it is possible to access the user data in the information system by querying with CRM classes and properties so that the meaning of the answers to the queries corresponds to the query terms used. It is not regarded as a reduction of compatibility if access is limited to data deemed to be exchanged.

 

An information system is partially access-compatible with the CRM if it is possible to access the user data in the information system by querying with a consistent subset of CRM classes and properties, corresponding to a reduced CRM-compatible form, so that the meaning of the answers to the queries corresponds to the query terms used.

 

An access-compatible system may be export-compatible with respect to the query answers. Note that it may make sense for an access-compatible content management system to return only content items in response to queries rather than being export compatible.

 

 

fig. 1 : Possible data flow between different kinds of CRM-compatible systems and data structures

 

Fig. 1 shows a symbolic representation of some of the data flow patterns defined above between different kinds of CRM-compatible systems and data structures. In this figure it is assumed that the Local System B exports data into a CRM export-compatible data structure, which implies that it can be exported into a CRM-compatible form or any other CRM import-compatible data structure. Therefore Local System B is export-compatible with the CRM. For Local System A, the figure symbolizes the case where the exported data contain elements that correspond to specializations of the CRM or fall out of its scope.

Compatibility claim declaration

 

A provider of a data structure or information system claiming compatibility with the CRM has to provide a declaration that describes the kind of compatibility and, depending on the kind, the following additional information: 

·         For  export-compatible data structures:

The subset of CRM concepts directly instantiated by any possible data in this data structure after transformation into a CRM-compatible form.

·         For export-compatible systems:

a.       A declaration of configurable user data elements, if any, that are not semantically restricted to  a CRM Concept (other than E1 CRM Entity or E77 Persistent Item).

b.       User data elements or units that are not exported.

c.       The subset of CRM concepts directly instantiated by any possible data exported from the system after transformation into a CRM-compatible form.

·         For partially or dedicated import-compatible systems:

The subset of CRM concepts under which data can be imported into the system.

·         For  access-compatible systems:

a.       The query language by which the system can be queried.

b.       The subset of CRM concepts directly instantiated by any possible query answers exported from the system after transformation into a CRM-compatible form.

c.       For partially access-compatible systems, the subset of CRM concepts by which the system can be queried.

 

The provider should be able to demonstrate the claim with suitable test data. The provider should be able to demonstrate its claim according to certain procedures included in any applicable certificate practice related statement.

The provider should either make evidence of these procedures publicly available on the Internet on a site nominated by the ISO community of use, so that any third party is able to verify the claim with suitable test data, or acquire a certificate by a certification authority (CA).

A trusted third party recognised and authorised by a competent regulatory authority to act as a CA in this practice area, should be able to verify the credentials of the provider applying for such certificate and thus, of its claim with suitable test data, before issuing the certificate so that the users can trust the information in the CA certificates.

The CA will grant the provider of the certified system the right to use the “CRM compatible” logo..

 

Applied Form

The CRM is an ontology in the sense used in computer science. It has been expressed as an object-oriented semantic model, in the hope that this formulation will be comprehensible to both documentation experts and information scientists alike, while at the same time being readily converted to machine-readable formats such as RDF Schema, KIF, DAML+OIL, OWL, STEP, etc. It can be implemented in any Relational or object-oriented schema. CRM instances can also be encoded in RDF, XML, DAML+OIL, OWL and others.

 

Although the definition of the CRM provided here is complete, it is an intentionally compact and concise presentation of the CRM’s 86 classes and 137 unique properties. It does not attempt to articulate the inheritance of properties by subclasses throughout the class hierarchy (this would require the declaration of several thousand properties, as opposed to 137). However, this definition does contain all of the information necessary to infer and automatically generate a full declaration of all properties, including inherited properties.

Terminology

The following definitions of key terminology used in this document are provided both as an aid to readers unfamiliar with object-oriented modelling terminology, and to specify the precise usage of terms that are sometimes applied inconsistently across the object oriented modelling community for the purpose of this document. Where applicable, the editors have tried to consistently use terminology that is compatible with that of the Resource Description Framework (RDF) [3] , a recommendation of the World Wide Web Consortium. The editors have tried to find a language which is comprehensible to the non-computer expert and precise enough for the computer expert so that both understand the intended meaning.

 

Class

A class is a category of items that share one or more common traits serving as criteria to identify the items belonging to the class. These properties need not be explicitly formulated in logical terms, but may be described in a text (here called a scope note ) that refers to a common conceptualisation of domain experts. The sum of these traits is called the intension of the class. A class may be the domain or range of none, one or more properties formally defined in a model. The formally defined properties need not be part of the intension of their domains or ranges: such properties are optional. An item that belongs to a class is called an instance of this class. A class is associated with an open set of real life instances, known as the extension of the class. Here “open” is used in the sense that it is generally beyond our capabilities to know all instances of a class in the world and indeed that the future may bring new instances about at any time ( Open World ). Therefore a class cannot be defined by enumerating its instances. A class plays a role analogous to a grammatical noun, and can be completely defined without reference to any other construct (unlike properties , which must have an unambiguously defined domain and range). In some contexts, the terms individual class, entity or node are used synonymously with class.

For example:

Person is a class. To be a Person may actually be determined by DNA characteristics, but we all know what a Person is. A Person may have the property of being a member of a Group, but it is not necessary to be member of a Group in order to be a Person. We shall never know all Persons of the past. There will be more Persons in the future.

 

subclass

A subclass is a class that is a specialization of another class (its superclass ). Specialization or the IsA relationship means that:

1.       all instances of the subclass are also instances of its superclass,

2.       the intension of the subclass extends the intension of its superclass, i.e. its traits are more restrictive than that of its superclass and

3.       the subclass inherits the definition of all of the properties declared for its superclass without exceptions ( strict inheritance ), in addition to having none, one or more properties of its own.

 

A subclass can have more than one immediate superclass and consequently inherits the properties of all of its superclasses ( multiple inheritance ). The IsA relationship or specialization between two or more classes gives rise to a structure known as a class hierarchy. The IsA relationship is transitive and may not be cyclic. In some contexts (e.g. the programming language C++) the term derived class is used synonymously with subclass.

 

For example:

Every Person IsA Biological Object, or Person is a subclass of Biological Object.

Also, every Person IsA Actor. A Person may die. However other kinds of Actors, such as companies, don’t die (c.f. 2).

Every Biological Object IsA Physical Object. A Physical Object can be moved. Hence a Person can be moved also (c.f. 3).

 

superclass

A superclass is a class that is a generalization of one or more other classes (its subclasses ), which means that it subsumes all instances of its subclasses, and that it can also have additional instances that do not belong to any of its subclasses. The intension of the superclass is less restrictive than any of its subclasses. This subsumption relationship or generalization is the inverse of the IsA relationship or specialization.

In some contexts (e.g. the programming language C++) the term parent class is used synonymously with superclass.

 

For example:

“Biological Object subsumes Person” is synonymous with “Biological Object is a superclass of Person”. It needs fewer traits to identify an item as a Biological Object than to identify it as a Person.

 

intension

The intension of a class or property is its intended meaning. It consists of one or more common traits shared by all instances of the class or property. These traits need not be explicitly formulated in logical terms, but may just be described in a text (here called a scope note ) that refers to a conceptualisation common to domain experts. In particular the so-called primitive concepts, which make up most of the CRM, cannot be further reduced to other concepts by logical terms.

 

extension

The extension of a class is the set of all real life instances belonging to the class that fulfil the criteria of its intension . This set is “open” in the sense that it is generally beyond our capabilities to know all instances of a class in the world and indeed that the future may bring new instances about at any time ( Open World ). An information system may at any point in time refer to some instances of a class, which form a subset of its extension.

 

scope note

A scope note is a textual description of the intension of a class or property.

Scope notes are not formal modelling constructs, but are provided to help explain the intended meaning and application of the CRM’s classes and properties. Basically, they refer to a conceptualisation common to domain experts and disambiguate between different possible interpretations. Illustrative example instances of classes and properties are also regularly provided in the scope notes for explanatory purposes.

 

instance

An instance of a class is a real world item that fulfils the criteria of the intension of the class. Note, that the number of instances declared for a class in an information system is typically less than the total in the real world. For example, you are an instance of Person, but you are not mentioned in all information systems describing Persons.

For example:

The painting known as the “The Mona Lisa” is an instance of the class Man Made Object.

 

An instance of a property is a factual relation between an instance of the domain and an instance of the range of the property that matches the criteria of the intension of the property.

 

For example:

“The Louvre is current owner of The Mona Lisa” is an instance of the property “ is current owner of”.

 

property

A property serves to define a relationship of a specific kind between two classes. The property is characterized by an intension , which is conveyed by a scope note. A property plays a role analogous to a grammatical verb, in that it must be defined with reference to both its domain and range , which are analogous to the subject and object in grammar (unlike classes, which can be defined independently). It is arbitrary, which class is selected as the domain, just as the choice between active and passive voice in grammar is arbitrary. In other words, a property can be interpreted in both directions, with two distinct, but related interpretations. Properties may themselves have properties that relate to other classes (This feature is used in this model only in order to describe dynamic subtyping of properties). Properties can also be specialized in the same manner as classes, resulting in IsA relationships between subproperties and their superproperties .

In some contexts, the terms attribute, reference, link, role or slot are used synonymously with property.

 

For example:

“Physical Man-Made Thing depicts CRM Entity” is equivalent to “CRM Entity is depicted by Physical Man-Made Thing”.

 

subproperty

 

A subproperty is a property that is a specialization of another property (its superproperty ). Specialization or IsA relationship means that:

1.       all instances of the subproperty are also instances of its superproperty,

2.       the intension of the subproperty extends the intension of the superproperty, i.e. its traits are more restrictive than that of its superproperty,

3.       the domain of the subproperty is the same as the domain of its superproperty or a subclass of that domain,

4.       the range of the subproperty is the same as the range of its superproperty or a subclass of that range,

5.       the subproperty inherits the definition of all of the properties declared for its superproperty without exceptions ( strict inheritance ), in addition to having none, one or more properties of its own.

 

A subproperty can have more than one immediate superproperty and consequently inherits the properties of all of its superproperties ( multiple inheritance ). The IsA relationship or specialization between two or more properties gives rise to the structure we call a property hierarchy. The IsA relationship is transitive and may not be cyclic.

Some object-oriented languages, such as C++, have no equivalent to the specialization of properties.

 

superproperty

 

A superproperty is a property that is a generalization of one or more other properties (its subproperties ), which means that it subsumes all instances of its subproperties, and that it can also have additional instances that do not belong to any of its subproperties. The intension of the superproperty is less restrictive than any of its subproperties. The subsumption relationship or generalization is the inverse of the IsA relationship or specialization.

 

domain

The domain is the class for which a property is formally defined. This means that instances of the property are applicable to instances of its domain class. A property must have exactly one domain, although the domain class may always contain instances for which the property is not instantiated. The domain class is analogous to the grammatical subject of the phrase for which the property is analogous to the verb. It is arbitrary, which class is selected as the domain and which as the range , just as the choice between active and passive voice in grammar is arbitrary. Property names in the CRM are designed to be semantically meaningful and grammatically correct when read from domain to range . In addition, the inverse property name, normally given in parentheses, is also designed to be semantically meaningful and grammatically correct when read from range to domain.

 

range

The range is the class that comprises all potential values of a property. That means that instances of the property can link only to instances of its range class. A property must have exactly one range, although the range class may always contain instances that are not the value of the property. The range class is analogous to the grammatical object of a phrase for which the property is analogous to the verb. It is arbitrary, which class is selected as domain and which as range, just as the choice between active and passive voice in grammar is arbitrary. Property names in the CRM are designed to be semantically meaningful and grammatically correct when read from domain to range . In addition the inverse property name, normally given in parentheses, is also designed to be semantically meaningful and grammatically correct when read from range to domain.

 

inheritance

Inheritance of properties from superclasses to subclasses means that if an item x is an instance of a class A, then

1.       all properties that must hold for the instances of any of the superclasses of A must also hold for item x, and

all optional properties that may hold for the instances of any of the superclasses of A may also hold for item x.

 

strict

inheritance

Strict inheritance means that there are no exceptions to the inheritance of properties from superclasses to subclasses . For instance, some systems may declare that elephants are grey, and regard a white elephant as an exception. Under strict inheritance it would hold that: if all elephants were grey, then a white elephant could not be an elephant. Obviously not all elephants are grey. To be grey is not part of the intension of the concept elephant but an optional property. The CRM applies strict inheritance as a normalization principle.

 

multiple

inheritance

Multiple inheritance means that a class A may have more than one immediate superclass . The extension of a class with multiple immediate superclasses is a subset of the intersection of all extensions of its superclasses. The intension of a class with multiple immediate superclasses extends the intensions of all its superclasses, i.e. its traits are more restrictive than any of its superclasses. If multiple inheritance is used, the resulting “class hierarchy” is a directed graph and not a tree structure. If it is represented as an indented list, there are necessarily repetitions of the same class at different positions in the list.

For example, Person is both, an Actor and a Biological Object.

 

endurant, perdurant

“The difference between enduring and perduring entities (which we shall also call endurants and perdurants ) is related to their behaviour in time. Endurants are wholly present (i.e., all their proper parts are present) at any time they are present. Perdurants, on the other hand, just extend in time by accumulating different temporal parts, so that, at any time they are present, they are only partially present, in the sense that some of their proper temporal parts (e.g., their previous or future phases) may be not present. E.g., the piece of paper you are reading now is wholly present, while some temporal parts of your reading are not present any more. Philosophers say that endurants are entities that are in time, while lacking however temporal parts (so to speak, all their parts flow with them in time). Perdurants, on the other hand, are entities that happen in time, and can have temporal parts (all their parts are fixed in time).” (Gangemi et al. 2002, pp. 166-181).

 

shortcut

A shortcut is a formally defined single property that represents a deduction or join of a data path in the CRM. The scope notes of all properties characterized as shortcuts describe in words the equivalent deduction. Shortcuts are introduced for the cases where common documentation practice refers only to the deduction rather than to the fully developed path. For example, museums often only record the dimension of an object without documenting the Measurement that observed it. The CRM allows shortcuts as cases of less detailed knowledge, while preserving in its schema the relationship to the full information.

 

monotonic

reasoning

Monotonic reasoning is a term from knowledge representation. A reasoning form is monotonic if an addition to the set of propositions making up the knowledge base never determines a decrement in the set of conclusions that may be derived from the knowledge base via inference rules. In practical terms, if experts enter subsequently correct statements to an information system, the system should not regard any results from those statements as invalid, when a new one is entered. The CRM is designed for monotonic reasoning and so enables conflict-free merging of huge stores of knowledge.

 

disjoint

Classes are disjoint if the intersection of their extensions is an empty set. In other words, they have no common instances in any possible world.

 

primitive

The term primitive as used in knowledge representation characterizes a concept that is declared and its meaning is agreed upon, but that is not defined by a logical deduction from other concepts. For example, mother may be described as a female human with child. Then mother is not a primitive concept. Event however is a primitive concept.

Most of the CRM is made up of primitive concepts.

 

Open World

The “Open World Assumption” is a term from knowledge base systems. It characterizes knowledge base systems that assume the information stored is incomplete relative to the universe of discourse they intend to describe. This incompleteness may be due to the inability of the maintainer to provide sufficient information or due to more fundamental problems of cognition in the system’s domain. Such problems are characteristic of cultural information systems. Our records about the past are necessarily incomplete. In addition, there may be items that cannot be clearly assigned to a given class .

In particular, absence of a certain property for an item described in the system does not mean that this item does not have this property. For example, if one item is described as Biological Object and another as Physical Object, this does not imply that the latter may not be a Biological Object as well. Therefore complements of a class with respect to a superclass cannot be concluded in general from an information system using the Open World Assumption. For example, one cannot list “all Physical Objects known to the system that are not Biological Objects in the real world”, but one may of course list “all items known to the system as Physical Objects but that are not known to the system as Biological Objects”.

 

complement

The complement of a class A with respect to one of its superclasses B is the set of all instances of B that are not instances of A. Formally, it is the set-theoretic difference of the extension of B minus the extension of A. Compatible extensions of the CRM should not declare any class with the intension of them being the complement of one or more other classes. To do so will normally violate the desire to describe an Open World . For example, for all possible cases of human gender, male should not be declared as the complement of female or vice versa. What if someone is both or even of another kind?

 

query containment

Query containment is a problem from database theory: A query X contains another query Y, if for each possible population of a database the answer set to query X contains also the answer set to query Y. If query X and Y were classes, then X would be superclass of Y.

 

interoperability

Interoperability means the capability of different information systems to communicate some of their contents. In particular, it may mean that

1.       two systems can exchange information, and/or

2.       multiple systems can be accessed with a single method.

 

Generally, syntactic interoperability is distinguished from semantic interoperability . Syntactic interoperability means that the information encoding of the involved systems and the access protocols are compatible, so that information can be processed as described above without error. However, this does not mean that each system processes the data in a manner consistent with the intended meaning. For example, one system may use a table called “Actor” and another one called “Agent”. With syntactic interoperability, data from both tables may only be retrieved as distinct, even though they may have exactly the same meaning. To overcome this situation, semantic interoperability has to be added. The CRM relies on existing syntactic interoperability and is concerned only with adding semantic interoperability .

 

semantic interoperability

Semantic interoperability means the capability of different information systems to communicate information consistent with the intended meaning. In more detail, the intended meaning encompasses

1.       the data structure elements involved,

2.       the terminology appearing as data and

3.       the identifiers used in the data for factual items such as places, people, objects etc.

 

Obviously communication about data structure must be resolved first. In this case consistent communication means that data can be transferred between data structure elements with the same intended meaning or that data from elements with the same intended meaning can be merged. In practice, the different levels of generalization in different systems do not allow the achievement of this ideal. Therefore semantic interoperability is regarded as achieved if elements can be found that provide a reasonably close generalization for the transfer or merge. This problem is being studied theoretically as the query containment problem. The CRM is only concerned with semantic interoperability on the level of data structure elements.

 

property quantifiers

We use the term property quantifiers for the declaration of the allowed number of instances of a certain property that an instance of its range or domain may have. These declarations are ontological, i.e. they refer to the nature of the real world described and not to our current knowledge. For example, each person has exactly one father, but collected knowledge may refer to none, one or many.

 

universal

The fundamental ontological distinction between universals and particulars can be informally understood by considering their relationship with instantiation: particulars are entities that have no instances in any possible world; universals are entities that do have instances. Classes and properties (corresponding to predicates in a logical language) are usually considered to be universals. (after Gangemi et al. 2002, pp. 166-181).

 

Property Quantifiers

Quantifiers for properties are provided for the purpose of semantic clarification only, and should not be treated as implementation recommendations. The CRM has been designed to accommodate alternative opinions and incomplete information, and therefore all properties should be implemented as optional and repeatable for their domain and range (“many to many (0,n:0,n)”). Therefore the term “cardinality constraints” is avoided here, as it typically pertains to implementations.

 

The following table lists all possible property quantifiers occurring in this document by their notation, together with an explanation in plain words. In order to provide optimal clarity, two widely accepted notations are used redundantly in this document, a verbal and a numeric one. The verbal notation uses phrases such as “one to many”, and the numeric one, expressions such as “(0,n:0,1)”. While the terms “one”, “many” and “necessary” are quite intuitive, the term “dependent” denotes a situation where a range instance cannot exist without an instance of the respective property. In other words, the property is “necessary” for its range.

 

many to many (0,n:0,n)

Unconstrained: An individual domain instance and range instance of this property can have zero, one or more instances of this property. In other words, this property is optional and repeatable for its domain and range.

 

one to many

(0,n:0,1)

 

An individual domain instance of this property can have zero, one or more instances of this property, but an individual range instance cannot be referenced by more than one instance of this property. In other words, this property is optional for its domain and range, but repeatable for its domain only. In some contexts this situation is called a “fan-out”.

 

many to one

(0,1:0,n)

An individual domain instance of this property can have zero or one instance of this property, but an individual range instance can be referenced by zero, one or more instances of this property. In other words, this property is optional for its domain and range, but repeatable for its range only. In some contexts this situation is called a “fan-in”.

 

many to many, necessary (1,n:0,n)

An individual domain instance of this property can have one or more instances of this property, but an individual range instance can have zero, one or more instances of this property. In other words, this property is necessary and repeatable for its domain, and optional and repeatable for its range.

 

one to many, necessary

(1,n:0,1)

 

An individual domain instance of this property can have one or more instances of this property, but an individual range instance cannot be referenced by more than one instance of this property. In other words, this property is necessary and repeatable for its domain, and optional but not repeatable for its range. In some contexts this situation is called a “fan-out”.

 

many to one, necessary

(1,1:0,n)

An individual domain instance of this property must have exactly one instance of this property, but an individual range instance can be referenced by zero, one or more instances of this property. In other words, this property is necessary and not repeatable for its domain, and optional and repeatable for its range. In some contexts this situation is called a “fan-in”.

 

one to many, dependent

(0,n:1,1)

 

An individual domain instance of this property can have zero, one or more instances of this property, but an individual range instance must be referenced by exactly one instance of this property. In other words, this property is optional and repeatable for its domain, but necessary and not repeatable for its range. In some contexts this situation is called a “fan-out”.

 

one to many, necessary, dependent

(1,n:1,1)

An individual domain instance of this property can have one or more instances of this property, but an individual range instance must be referenced by exactly one instance of this property. In other words, this property is necessary and repeatable for its domain, and necessary but not repeatable for its range. In some contexts this situation is called a “fan-out”.

 

many to one, necessary, dependent

(1,1:1,n)

An individual domain instance of this property must have exactly one instance of this property, but an individual range instance can be referenced by one or more instances of this property. In other words, this property is necessary and not repeatable for its domain, and necessary and repeatable for its range. In some contexts this situation is called a “fan-in”.

 

one to one

(1,1:1,1)

An individual domain instance and range instance of this property must have exactly one instance of this property. In other words, this property is necessary and not repeatable for its domain and for its range.

 

The CRM defines some properties as being necessary for their domain or as being dependent from their range, following the definitions in the table above. Note that if such a property is not specified for an instance of the respective domain or range, it means that the property exists, but the value on one side of the property is unknown. In the case of optional properties, the methodology proposed by the CRM does not distinguish between a value being unknown or the property not being applicable at all. For example, one may know that an object has an owner, but the owner is unknown. In a CRM instance this case cannot be distinguished from the fact that the object has no owner at all. Of course, such details can always be specified by a textual note.

Naming Conventions

The following naming conventions have been applied throughout the CRM:

 

·      Classes are identified by numbers preceded by the letter “E” (historically classes were sometimes referred to as “Entities”), and are named using noun phrases (nominal groups) using title case (initial capitals). For example, E63 Beginning of Existence.

·      Properties are identified by numbers preceded by the letter “P,” and are named in both directions using verbal phrases in lower case. Properties with the character of states are named in the present tense, such as “has type”, whereas properties related to events are named in past tense, such as “carried out.” For example, P126 employed (was employed in) .

·      Property names should be read in their non-parenthetical form for the domain-to-range direction, and in parenthetical form for the range-to-domain direction.

·      Properties with a range that is a subclass of E59 Primitive Value (such as E1 CRM Entity. P3 has note: E62 String , for example) have no parenthetical name form, because reading the property name in the range-to-domain direction is not regarded as meaningful.

·      Properties that have identical domain and range are either symmetric or transitive. Instantiating a symmetric property implies that the same relation holds for both the domain-to-range and the range-to-domain directions. An example of this is E53 Place . P122 borders with: E53 Place . The names of symmetric properties have no parenthetical form, because reading in the range-to-domain direction is the same as the domain-to-range reading. Transitive asymmetric properties, such as E4 Period. P9 consist of (forms part of): E4 Period , have a parenthetical form that relates to the meaning of the inverse direction.

·      The choice of the domain of properties, and hence the order of their names, are established in accordance with the following priority list:

·           Temporal Entity and its subclasses

·           Thing and its subclasses

·           Actor and its subclasses

·           Other

 

Modelling principles

 

The following modelling principles have guided and informed the development of the CIDOC CRM.

Monotonicity

Because the CRM’s primary role is the meaningful integration of information in an Open World, it aims to be monotonic in the sense of Domain Theory. That is, the existing CRM constructs and the deductions made from them must always remain valid and well-formed, even as new constructs are added by extensions to the CRM.

 

For example:

One may add a subclass of E7 Activity to describe the practice of an instance of group to use a certain name for a place over a certain time-span. By this extension, no existing IsA Relationships or property inheritances are compromised.

 

In addition, the CRM aims to enable the formal preservation of monotonicity when augmenting a particular CRM compatible system. That is, existing CRM instances, their properties and deductions made from them, should always remain valid and well-formed, even as new instances, regarded as consistent by the domain expert, are added to the system.

 

For example:

If someone describes correctly that an item is an instance of E19 Physical Object, and later it is correctly characterized as an instance of E20 Biological Object, the system should not stop treating it as an instance of E19 Physical Object.

 

In order to formally preserve monotonicity for the frequent cases of alternative opinions, all formally defined properties should be implemented as unconstrained ( many: many ) so that conflicting instances of properties are merely accumulated. Thus knowledge integrated following the CRM serves as a research base, accumulating relevant alternative opinions around well-defined entities, whereas conclusions about the truth are the task of open-ended scientific or scholarly hypothesis building.

 

For example:

El Greco and even King Arthur should always remain an instance of E21 Person and be dealt with as existing within the sense of our discourse, once they are entered into our knowledge base. Alternative opinions about properties, such as their birthplaces and their living places, should be accumulated without validity decisions being made during data compilation.

Minimality

Although the scope of the CRM is very broad, the model itself is constructed as economically as possible.

 

·           A class is not declared unless it is required as the domain or range of a property not appropriate to its superclass, or it is a key concept in the practical scope.

·           CRM classes and properties that share a superclass are non-exclusive by default. For example, an object may be both an instance of E20 Biological Object and E22 Man-made Object.

·           CRM classes and properties are either primitive, or they are key concepts in the practical scope.

·           Complements of CRM classes are not declared.

Shortcuts

Some properties are declared as shortcuts of longer, more comprehensively articulated paths that connect the same domain and range classes as the shortcut property via one or more intermediate classes. For example, the property E18 Physical Thing. P52 has current owner (is current owner of): E39 Actor , is a shortcut for a fully articulated path from E18 Physical Thing through E8 Acquisition to E39 Actor. An instance of the fully-articulated path always implies an instance of the shortcut property. However, the inverse may not be true; an instance of the fully-articulated path cannot always be inferred from an instance of the shortcut property.

 

The class E13 Attribute Assignment allows for the documentation of how the assignment of any property came about, and whose opinion it was, even in cases of properties not explicitly characterized as “shortcuts”.

Disjointness

Classes are disjoint if they share no common instances in any possible world. There are many examples of disjoint classes in the CRM.

 

A comprehensive declaration of all possible disjoint class combinations afforded by the CRM has not been provided here; it would be of questionable practical utility, and may easily become inconsistent with the goal of providing a concise definition. However, there are two key examples of disjoint class pairs that are fundamental to effective comprehension of the CRM:

 

·           E2 Temporal Entity is disjoint from E77 Persistent Item. Instances of the class E2 Temporal Entity are perdurants, whereas instances of the class E77 Persistent Item are endurants. Even though instances of E77 Persistent Item have a limited existence in time, they are fundamentally different in nature from instances of E2 Temporal Entity, because they preserve their identity between events. Declaring endurants and perdurants as disjoint classes is consistent with the distinctions made in data structures that fall within the CRM’s practical scope.

·           E18 Physical Thing is disjoint from E28 Conceptual Object. The distinction is between material and immaterial items, the latter being exclusively man-made. Instances of E18 Physical Thing and E28 Conceptual Object differ in many fundamental ways; for example, the production of instances of E18 Physical Thing implies the incorporation of physical material, whereas the production of instances of E28 Conceptual Object does not. Similarly, instances of E18 Physical Thing cease to exist when destroyed, whereas an instance of E28 Conceptual Object perishes when it is forgotten or its last physical carrier is destroyed.

About Types

Virtually all structured descriptions of museum objects begin with a unique object identifier and information about the "type" of the object, often in a set of fields with names like "Classification", "Category", "Object Type", "Object Name", etc. All these fields are used for terms that declare that the object belongs to a particular category of items. In the CRM the class E55 Type comprises such terms from thesauri and controlled vocabularies used to characterize and classify instances of CRM classes.  Instances of E55 Type represent concepts (universals) in contrast to instances of E41 Appellation which are used to name instances of CRM classes.

 

E55 Type is the CRM’s interface to domain specific ontologies and thesauri. These can be represented in the CRM as subclasses of E55 Type, forming hierarchies of terms, i.e. instances of E55 Type linked via P127 has broader term (has narrower term) . Such hierarchies may be extended with additional properties.

 

For this purpose the CRM provides two basic properties that describe classification with terminology, corresponding to what is the current practice in the majority of information systems. The class E1 CRM Entity is the domain of the property P2 has type (is type of), which has the range E55 Type. Consequently, every class in the CRM, with the exception of E59 Primitive Value, inherits the property P2 has type (is type of).  This provides a general mechanism for simulating a specialization of the classification of CRM instances to any level of detail, by linking to external vocabulary sources, thesauri, classification schema or ontologies.

 

Analogous to the function of the P2 has type (is type of) property, some properties in the CRM are associated with an additional property. These are numbered in the CRM documentation with a ‘.1’ extension. The range of these properties of properties always falls under E55 Type. Their purpose is to simulate a specialization of their parent property through the use of property subtypes declared as instances of E55 Type. They do not appear in the property hierarchy list but are included as part of the property declarations and referred to in the class declarations. For example, P62.1 mode of depiction: E55 Type is associated with E24 Physical Man-made Thing. P62 depicts (is depicted by): E1 CRM Entity.

 

The class E55 Type also serves as the range of properties that relate to categorical knowledge commonly found in cultural documentation. For example, the property P125 used object of type (was type of object used in) enables the CRM to express statements such as “this casting was produced using a mould”, meaning that there has been an unknown or unmentioned object, a mould, that was actually used. This enables the specific instance of the casting to be associated with the entire type of manufacturing devices known as moulds. Further, the objects of type “mould” would be related via P2 has type (is type of) to this term. This indirect relationship may actually help in detecting the unknown object in an integrated environment. On the other side, some casting may refer directly to a known mould via P16 used specific object (was used for) .  So a statistical question to how many objects in a certain collection are made with moulds could be answered correctly (following both paths through P16 used specific object (was used for) - P2 has type (is type of) and P125 used object of type (was type of object used in ). This consistent treatment of categorical knowledge enhances the CRM’s ability to integrate cultural knowledge.

 

In addition to being an interface to external thesauri and classification systems E55 Type is an ordinary class in the CRM and a subclass of E28 Conceptual Object. E55 Type and its subclasses inherit all properties from this superclass.  Thus together with the CRM class E83 Type Creation the rigorous scholarly or scientific process that ensures a type is exhaustively described and appropriately named can be modelled inside the CRM. In some cases, particularly in archaeology and the life sciences, E83 Type Creation requires the identification of an exemplary specimen and the publication of the type definition in an appropriate scholarly forum. This is very central to research in the life sciences, where a type would be referred to as a “taxon,” the type description as a “protologue,” and the exemplary specimens as “original element” or “holotype”.

 

Finally, types, that is, instances of E55 Type and its subclasses, are used to characterize the instances of a CRM class and hence refine the meaning of the class.  A type ‘artist’ can be used to characterize persons through P2 has type (is type of). On the other hand, in an art history application of the CRM it can be adequate to extend the CRM class E21 Person with a subclass E21.xx Artist . What is the difference of the type ‘artist’ and the class Artist? From an everyday conceptual point of view there is no difference. Both denote the concept ‘artist’ and identify the same set of persons. Thus in this setting a type could be seen as a class and the class of types may be seen as a metaclass.  Since current systems do not provide an adequate control of user defined metaclasses, the CRM prefers to model instances of E55 Type as if they were particulars, with the relationships described in the previous paragraphs.

 

Users may decide to implement a concept either as a subclass extending the CRM class system or as an instance of E55 Type. A new subclass should only be created in case the concept is sufficiently stable and associated with additional explicitly modelled properties specific to it. Otherwise, an instance of E55 Type provides more flexibility of use. Users that may want to describe a discourse not only using a concept extending the CRM but also describing the history of this concept itself, may chose to model the same concept both as subclass and as an instance of E55 Type with the same name. Similarly it should be regarded as good practice to foresee for each term hierarchy refining a CRM class a term equivalent of this class as top term. For instance, a term hierarchy for instances of E21 Person may begin with “Person”.

 

Extensions

Since the intended scope of the CRM is a subset of the “real” world and is therefore potentially infinite, the model has been designed to be extensible through the linkage of compatible external type hierarchies.

 

Compatibility of extensions with the CRM means that data structured according to an extension must also remain valid as a CRM instance. In practical terms, this implies query containment: any queries based on CRM concepts should retrieve a result set that is correct according to the CRM’s semantics, regardless of whether the knowledge base is structured according to the CRM’s semantics alone, or according to the CRM plus compatible extensions. For example, a query such as “list all events” should recall 100% of the instances deemed to be events by the CRM, regardless of how they are classified by the extension.

 

A sufficient condition for the compatibility of an extension with the CRM is that CRM classes subsume all classes of the extension, and all properties of the extension are either subsumed by CRM properties, or are part of a path for which a CRM property is a shortcut. Obviously, such a condition can only be tested intellectually.

Coverage

Of necessity, some concepts covered by the CRM are less thoroughly elaborated than others: E39 Actor and E30 Right, for example. This is a natural consequence of staying within the CRM’s clearly articulated practical scope in an intrinsically unlimited domain of discourse. These ‘underdeveloped’ concepts can be considered as hooks for compatible extensions.

 

The CRM provides a number of mechanisms to ensure that coverage of the intended scope is complete:

1.       Existing high level classes can be extended, either structurally as subclasses or dynamically using the type hierarchy.

2.       Existing high level properties can be extended, either structurally as subproperties, or in some cases, dynamically, using properties of properties which allow subtyping.

3.       Additional information that falls outside the semantics formally defined by the CRM can be recorded as unstructured data using E1 CRM Entity. P3 has note: E62 String .

 

In mechanisms 1 and 2 the CRM concepts subsume and thereby cover the extensions.

 

In mechanism 3, the information is accessible at the appropriate point in the respective knowledge base. This approach is preferable when detailed, targeted queries are not expected; in general, only those concepts used for formal querying need to be explicitly modelled.

 

Examples

fig. 2 reasoning about spatial information

 

The diagram above shows a partial view of the CRM, representing reasoning about spatial information. Five of the main hierarchy branches are included in this view: E39 Actor, E51 Contact Point, E41 Appellation, E53 Place , and E70 Thing. The relationships between these main classes and their subclasses are shown as arrows. Properties between classes are shown as green rectangles. A ‘shortcut’ property is included in this view: P59 has section (is located on or within) between E53 Place and E18 Physical Thing is a shortcut of the path through E46 Section Definition. In some cases the order of priority for property names has been modified in order to facilitate reading the diagram from left to right.

 

As can be seen, an instance of E53 Place is identified by an instance of E44 Place Appellation, which may be an instance of E45 Address, E47 Spatial Coordinates, E48 Place Name, or E46 Section Definition such as ‘basement’, ‘prow’, or ‘lower left-hand corner.’ An instance of E53 Place may consist of or form part of another instance of E53 Place, thereby allowing a hierarchy of physical ‘containers’ to be constructed.

 

An instance of E45 Address can be considered both as an E44 Place Appellation–a way of referring to an E53 Place–and as an E51 Contact Point for an E39 Actor. An E39 Actor may have any number of instances of E51 Contact Point. E18 Physical Thing is found on locations as a consequence of being created there or being moved there. Therefore the properties P53 has former or current location (is former or current location of) ( and P55 has current location (currently holds) are regarded as shortcuts of the fully articulated paths through the respective events. P55 has current location (currently holds) is a subproperty of P53 has former or current location (is former or current location of) . The latter is a container for location information in the absence of knowledge about time of validity and related events.

 

An interesting aspect of the model is the P58 has section definition (defines section) property between E46 Section Definition and E18 Physical Thing (and the corresponding shortcut from E53 Place to E19 Physical Object). This allows an instance of E53 Place to be defined as a section of an instance of E19 Physical Object. For example, we may know that Nelson fell at a particular spot on the deck of H.M.S. Victory, without knowing the exact position of the vessel in geospatial terms at the time of the fatal shooting of Nelson. Similarly, a signature or inscription can be located “in the lower right corner of” a painting, regardless of where the painting is hanging.

 

fig. 3 reasoning about temporal information

 

This second example shows how the CRM handles reasoning about temporal information. Four of the main hierarchy branches are included in this view: E2 Temporal Entity, E52 Time-Span, E77 Persistent Item and E53 Place .

 

The E2 Temporal Entity class is an abstract class (i.e. it has no instances) that serves to group together all classes with a temporal component, such as instances of E4 Period, E5 Event and E3 Condition State.

 

An instance of E52 Time-Span is simply a temporal interval that does not make any reference to cultural or geographical contexts (unlike instances of E4 Period, which took place at a particular instance of E53 Place ). Instances of E52 Time-Span are sometimes identified by instances of E49 Time Appellation, often in the form of E50 Date.

 

Both E52 Time-Span and E4 Period have transitive properties. E52 Time-Span has the transitive property P86 falls within (contains), denoting a purely incidental inclusion; whereas E4 Period has the transitive property P9 consists of (forms part of) that supports the decomposition of instances of E4 Period into their constituent parts. For example, the E52 Time-Span during which a building is constructed might falls within the E52 Time-Span of a particular government, although there is no causal or contextual connection between the two instances of E52 Time-Span; conversely, the E4 Period of the Chinese Song Dynasty consists of the Northern Song Period and the Southern Song Period.

 

Instances of E52 Time-Span are related to their outer bounds (i.e. their indeterminacy interval) by the property P82 at some time within, and to their inner bounds via the property P81 ongoing throughout. The range of these properties is the E61 Time Primitive class, instances of which are treated by the CRM as application or system specific date intervals that are not further analysed.

Class & Property Hierarchies

Although they do not provide comprehensive definitions, compact monohierarchical presentations of the class and property IsA hierarchies have been found to significantly aid comprehension and navigation of the CRM, and are therefore provided below.

 

The class hierarchy presented below has the following format:

 

·         Each line begins with a unique class identifier, consisting of a number preceded by the letter “E” (originally denoting “entity,” although now replaced by convention with the term “class”).

·         A series of hyphens (“-”) follows the unique class identifier, indicating the hierarchical position of the class in the IsA hierarchy.

·         The English name of the class appears to the right of the hyphens.

·         The index is ordered by hierarchical level, in a “depth first” manner, from the smaller to the larger subhierarchies.

·         Classes that appear in more than one position in the class hierarchy as a result of multiple inheritance are shown in an italic typeface.

 

The property hierarchy presented below has the following format:

 

·         Each line begins with a unique property identifier, consisting of a number preceded by the letter “P” (for “property”).

·         A series of hyphens (“-”) follows the unique property identifier, indicating the hierarchical position of the property in the IsA hierarchy.

·         The English name of the property appears to the right of the hyphens, followed by its inverse name in parentheses for reading in the range to domain direction.

·         The domain class for which the property is declared.

·         The range class that the property references.

·         The index is ordered by hierarchical level, in a “depth first” manner, from the smaller to the larger subhierarchies, and by property number between equal siblings.

·         Properties that appear in more than one position in the property hierarchy as a result of multiple inheritance are shown in an italic typeface.


CIDOC CRM Class Hierarchy

 

E1

CRM Entity

E 2

-

Temporal Entity

E 3

-

-

Condition State  

E 4

-

-

Period

E5

-

-

-

Event

E7

-

-

-

-

Activity

E8

-

-

-

-

-

Acquisition Event

E9

-

-

-

-

-

Move

E10

-

-

-

-

-

Transfer of Custody

E11

-

-

-

-

-

Modification

E12

-

-

-

-

-

-

Production

E79

-

-

-

-

-

-

Part Addition

E80

-

-

-

-

-

-

Part Removal

E13

-

-

-

-

-

Attribute Assignment

E14

-

-

-

-

-

-

Condition Assessment

E15

-

-

-

-

-

-

Identifier Assignment

E16

-

-

-

-

-

-

Measurement

E17

-

-

-

-

-

-

Type Assignment

E65

-

-

-

-

-

Creation

E83

-

-

-

-

-

-

Type Creation

E6 6

-

-

-

-

-

Formation

E85

-

-

-

-

-

Joining

E86

-

-

-

-

-

Leaving

E87

-

-

-

-

-

Curation Activity

E63

-

-

-

-

Beginning of Existence

E67

-

-

-

-

-

Birth

E81

-

-

-

-

-

Transformation

E12

-

-

-

-

-

Production

E65

-

-

-

-

-

Creation

E83

-

-

-

-

-

-

Type Creation

E66

-

-

-

-

-

Formation

E64

-

-

-

-

End of Existence

E6

-

-

-

-

-

Destruction

E68

-

-

-

-

-

Dissolution

E69

-

-

-

-

-

Death

E81

-

-

-

-

-

Transformation

E77

-

Persistent Item

E70

-

-

Thing

E72

-

-

-

Legal Object

E18

-

-

-

-

Physical Thing

E19

-

-

-

-

-

Physical Object

E20

-

-

-

-

-

-

Biological Object

E21

-

-

-

-

-

-

-

Person

E22

-

-

-

-

-

-

Man-Made Object

E84

-

-

-

-

-

-

-

Information Carrier

E24

-

-

-

-

-

Physical Man-Made Thing

E22

-

-

-

-

-

-

Man-Made Object

E84

-

-

-

-

-

-

-

Information Carrier

E25

-

-

-

-

-

-

Man-Made Feature

E78

-

-

-

-

-

-

Collection

E26

-

-

-

-

-

Physical Feature

E27

-

-

-

-

-

-

Site

E25

-

-

-

-

-

-

Man-Made Feature

E90

-

-

-

-

Symbolic Object

E73

-

-

-

-

-

Information Object

E29

-

-

-

-

-

 

Design or Procedure

E31

-

-

-

-

-

 

Document

E32

-

-

-

-

-

-

-

Authority Document

E33

-

-

-

-

-

-

Linguistic Object

E34

-

-

-

-

-

-

-

Inscription

E35

-

-

-

-

-

-

-

Title

E36

-

-

-

-

-

 

Visual Item

E37

-

-

-

-

-

-

-

Mark

E34

-

-

-

-

-

-

-

-

Inscription

E38

-

-

-

-

-

-

-

Image

E41

-

-

-

-

-

Appellation

E42

-

-

-

-

-

-

Identifier

E44

-

-

-

-

-

-

Place Appellation

E45

-

-

-

-

-

-

-

Address

E46

-

-

-

-

-

-

-

Section Definition

E47

-

-

-

-

-

-

-

Spatial Coordinates

E48

-

-

-

-

-

-

-

Place Name

E49

-

-

-

-

-

-

Time Appellation

E50

-

-

-

-

-

-

-

Date

E75

-

-

-

-

-

-

Conceptual Object Appellation

E82

-

-

-

-

-

-

Actor Appellation

E51

 

 

 

 

 

 

Contact Point

E45

 

 

 

 

 

 

 

Address

E35

-

-

-

-

 

 

Title

E71

-

-

-

Man-Made Thing

E24

-

-

-

-

Physical Man-Made Thing

E22

-

-

-

-

-

Man-Made Object

E84

-

-

-

-

-

-

Information Carrier

E25

-

-

-

-

-

Man-Made Feature

E78

-

-

-

-

-

Collection

E28

-

-

-

-

Conceptual Object

E90

-

-

-

-

-

Symbolic Object

E73

-

-

-

-

-

-

Information Object

E29

-

-

-

-

-

-

-

Design or Procedure

E31

-

-

-

-

-

-

-

Document

E32

-

-

-

-

-

-

-

-

Authority Document

E33

-

-

-

-

-

-

 

Linguistic Object

E34

-

-

-

-

-

-

-

-

Inscription

E35

-

-

-

-

-

-

 

-

Title

E36

-

-

-

-

-

-

-

-

Visual Item

E37

-

-

-

-

-

-

-

-

Mark

E34

-

-

-

-

-

-

-

-

-

Inscription

E38

-

-

-

-

-

-

-

-

Image

E41

-

-

-

-

-

-

Appellation

E42

-

-

-

-

-

-

-

Identifier

E44

-

-

-

-

-

-

-

Place Appellation

E45

-

-

-

-

-

-

-

-

Address

E46

-

-

-

-

-

-

-

-

Section Definition

E47

-

-

-

-

-

-

-

-

Spatial Coordinates

E48

-

-

-

-

-

-

-

-

Place Name

E49

-

-

-

-

-

 

-

Time Appellation

E50

-

-

-

-

-

-

-

-

Date

E75

-

-

-

-

-

-

-

Conceptual Object Appellation

E82

-

-

-

-

-

-

-

Actor Appellation

E51

-

-

-

-

-

-

-

Contact Point

E45

-

-

-

-

-

-

-

-

Address

E35

-

-

-

-

 

 

-

Title

E89

 

 

 

 

 

Propositional Object

E73

-

-

-

-

-

-

Information Object

E29

-

-

-

-

-

-

-

Design or Procedure

E31

-

-

-

-

-

-

-

Document

E32

-

-

-

-

-

-

-

-

Authority Document

E33

-

-

-

-

-

-

-

Linguistic Object

E34

-

-

-

-

-

-

-

-

Inscription

E35

-

-

-

-

-

-

-

-

Title

E36

-

-

-

-

-

-

-

Visual Item

E37

-

-

-

-

-

-

-

-

Mark

E34

-

-

-

-

-

-

-

-

 

Inscription

E38

-

-

-

-

-

-

-

-

Image

E30

-

-

-

-

-

-

Right

E55

-

-

-

-

-

Type

E56

-

-

-

-

-

-

Language

E57

-

-

-

-

-

-

Material

E58

-

-

-

-

-

-

Measurement Unit

E39

-

-

Actor

E74

-

-

-

Group

E40

-

-

-

-

Legal Body

E21

-

-

-

Person

E52

-

Time-Span

E53

-

Place

E54

-

Dimension

E59

Primitive Value

E60

-

Number

E61

-

Time Primitive

E62

-

String


CIDOC CRM Property Hierarchy:

 

Property id
Property Name

Entity – Domain

Entity - Range

P1

is identified by (identifies)

E1 CRM Entity

E41 Appellation

P48

   -   has preferred identifier (is preferred identifier of)

E1 CRM Entity

E42 Identifier

P78

   -   is identified by (identifies)

E52 Time-Span

E49 Time Appellation

P87

   -   is identified by (identifies)

E53 Place

E44 Place Appellation

P102

   -   has title (is title of)

E71 Man-Made Thing

E35 Title

P131

   -   is identified by (identifies)

E39 Actor

E82 Actor Appellation

P2

has type (is type of)

E1 CRM Entity

E55 Type

P137

   -   exemplifies (is exemplified by)

E1 CRM Entity

E55 Type

P3

has note

E1 CRM Entity

E62 String

P79

   -   beginning is qualified by

E52 Time-Span

E62 String

P80

   -   end is qualified by

E52 Time-Span

E62 String

P4

has time-span (is time-span of)

E2 Temporal Entity

E52 Time-Span

P5

consists of (forms part of)

E3 Condition State

E3 Condition State

P7

took place at (witnessed)

E4 Period

E53 Place

P26

   -   moved to (was destination of)

E9 Move

E53 Place

P27

   -   moved from (was origin of)

E9 Move

E53 Place

P8

took place on or within (witnessed)

E4 Period

E19 Physical Object

P9

consists of (forms part of)

E4 Period

E4 Period

P10

falls within (contains)

E4 Period

E4 Period

P12

occurred in the presence of (was present at)

E5 Event

E77 Persistent Item

P11

   -   had participant (participated in)

E5 Event

E39 Actor

P14

   -   -   carried out by (performed)

E7 Activity

E39 Actor

P 2 2

   -   -   -   transferred title to (acquired title through)

E8 Acquisition

E39 Actor

P 2 3

   -   -   -   transferred title from (surrendered title through)

E8 Acquisition

E39 Actor

P28

   -   -   -   custody surrendered by (surrendered custody through)

E10 Transfer of Custody

E39 Actor

P29

   -   -   -   custody received by (received custody through)

E10 Transfer of Custody

E39 Actor

P96

   -   -   by mother (gave birth)

E67 Birth

E21 Person

P99

   -   -   dissolved (was dissolved by)

E68 Dissolution

E74 Group

P143

   -   -   joined (was joined by)

E85 Joining

E39 Actor

P144

   -   -   joined with (gained member by)

E85 Joining

E74 Group

P145

   -   -   separated (left by)

E86 Leaving

E39 Actor

P146

   -   -   separated from (lost member by)

E86 Leaving

E74 Group

P16

   -   used specific object (was used for)

E7 Activity

E70 Thing

P33

   -   -   used specific   technique (was   used   by)

E7 Activity

E29 Design or Procedure

P142

   -   -   used constituent (was used in)

E15 Identifier Assignment

E41 Appellation

P25

   -   moved (moved   by)

E9 Move

E19 Physical Object

P31

   -   has modified (was modified by)

E11 Modification

E24 Physical Man-Made Thing

P108

   -  -    has produced (was produced by)

E12 Production

E24 Physical Man-Made Thing

P110

   -   -   augmented (was augmented by)

E79 Part Addition

E24 Physical Man-Made Thing

P112

   -   -   diminished (was diminished by)

E80 Part Removal

E24 Physical Man-Made Thing

P92

   -   brought into existence (was brought into existence by)

E63 Beginning of Existence

E77 Persistent Item

P94

   -   -   has created (was created by)

E65 Creation

E28 Conceptual Object

P135

   -   -   -   created type (was created by)

E83 Type Creation

E55 Type

P95

   -   -   has formed (was formed by)

E66 Formation

E74 Group

P98

   -   -   brought into life (was born)

E67 Birth

E21 Person

P108

   -  -    has produced (was produced by)

E12 Production

E24 Physical Man-Made Thing

P123

   -   -   resulted in (resulted from)

E81 Transformation

E77 Persistent Item

P93

   -   took out of existence (was taken out of existence by)

E64 End of Existence

E77 Persistent Item

P13

   -   -   destroyed (was destroyed by)

E6 Destruction

E18 Physical Thing

P99

   -   -   dissolved (was dissolved by)

E68 Dissolution

E74 Group

P100

   -   -   was death of (died in)

E69 Death

E21 Person

P124

   -   -   transformed (was transformed by)

E81 Transformation

E77 Persistent Item

P142

   -   -   used constituent (was used in)

E15 Identifier Assignment

E41 Appellation

P15

was influenced by (influenced)

E7 Activity

E1 CRM Entity

P16

   -   used specific object (was used for)

E7 Activity

E70 Thing

P33

   -   -   used specific technique (was used by)

E11 Modification

E29 Design or Procedure

P142

   -   -   used constituent (was used in)

E15 Identifier Assignment

E41 Appellation

P17

   -   was  motivated by (motivated)

E7 Activity

E1 CRM Entity

P134

   -   continued (was continued by)

E7 Activity

E7 Activity

P136

   -   was based on (supported type creation)

E83 Type Creation

E1 CRM Entity

P19

was intended use of (was made for)

E7 Activity

E71 Man-Made Thing

P20

had specific purpose (was purpose of)

E7 Activity

E5 Event

P21

had general purpose (was purpose of)

E7 Activity

E55 Type

P24

transferred title of (changed ownership through)

E8 Acquisition

E18 Physical Thing

P30

transferred custody of (custody transferred through)

E10 Transfer of Custody

E18 Physical Thing

P43

has dimension (is   dimension   of)

E70 Thing

E54 Dimension

P44

has condition (is condition of)

E18 Physical Thing

E3 Condition State

P45

consists of (is incorporated in)

E18 Physical Thing

E57 Material

P46

is composed of (forms part of)

E18 Physical Thing

E18 Physical Thing

P56

   -   bears feature (is found on)

E19 Physical Object

E26 Physical Feature

P49

has former or current keeper (is former or current keeper of)

E18 Physical Thing

E39 Actor

P50

   -   has current keeper (is current keeper of)

E18 Physical Thing

E39 Actor

P51

has former or current owner (is former or current owner of)

E18 Physical Thing

E39 Actor

P52

   -   has current owner (is current owner of)

E18 Physical Thing

E39 Actor

P53

has former or current location (is former or current location of)

E18 Physical Thing

E53 Place

P55

   -   has current location (currently holds)

E19 Physical Object

E53 Place

P54

has current permanent location (is current permanent location of)

E19 Physical Object

E53 Place

P57

has number of parts

E19 Physical Object

E60 Number

P58

has section definition (defines section)

E18 Physical Thing

E46 Section Definition

P59

has section (is located on or within)

E18 Physical Thing

E53 Place

P62

depicts   (is   depicted   by)

E24 Physical Man-Made Thing

E1 CRM Entity

P67

refers to ( is referred to by)

E89 Propositional Object

E1 CRM Entity

P70

   -   documents (is documented in)

E31 Document

E1 CRM Entity

P71

   -   lists (is listed in)

E32 Authority Document

E55 Type

P129

   -   is about (is subject of)

E89 Propositional Object

E1 CRM Entity

P138

   -   represents (has representation)

E36 Visual Item

E1 CRM Entity

P68

foresees use of (use foreseen by)

E29 Design or Procedure

E57 Material

P69

is associated with

E29 Design or Procedure

E29 Design or Procedure

P72

has language (is language of)

E33 Linguistic Object

E56 Language

P74

has current or former residence (is current or former residence of)

E39 Actor

E53 Place

P75

possesses (is possessed by)

E39 Actor

E30 Right

P76

has contact point (provides access to)

E39 Actor

E51 Contact Point

P81

ongoing throughout

E52 Time-Span

E61 Time Primitive

P82

at some time within

E52 Time-Span

E61 Time Primitive

P83

had at least duration (was minimum duration of)

E52 Time-Span

E54 Dimension

P84

had at most duration (was maximum duration of)

E52 Time-Span

E54 Dimension

P86

falls within (contains)

E52 Time-Span

E52 Time-Span

P88

consists of (forms part of)

E53 Place

E53 Place

P89

falls within (contains)

E53 Place

E53 Place

P90

has value

E54 Dimension

E60 Number

P91

has unit (is unit of)

E54 Dimension

E58 Measurement Unit

P97

from father (was father for)

E67 Birth

E21 Person

P101

had as general use (was use of)

E70 Thing

E55 Type

P103

was intended for (was intention of)

E71 Man-Made Thing

E55 Type

P104

is subject to (applies to)

E72 Legal Object

E30 Right

P105

right held by (has right on)

E72 Legal Object

E39 Actor

P52

   -   has current owner (is current owner of)

E18 Physical Thing

E39 Actor

P106

is composed of (forms part of)

E90 Symbolic Object

E90 Symbolic Object

P107

has current or former member (is current or former member of)

E74 Group

E39 Actor

P109

has current or former curator (is current or former curator of)

E78 Collection

E39 Actor

P111

added (was added by)

E79 Part Addition

E18 Physical Thing

P113

removed (was removed by)

E80 Part Removal

E18 Physical Thing

P114

is equal in time to

E2 Temporal Entity

E2 Temporal Entity

P115

finishes (is finished by)

E2 Temporal Entity

E2 Temporal Entity

P116

starts (is started by)

E2 Temporal Entity

E2 Temporal Entity

P117

occurs during (includes)

E2 Temporal Entity

E2 Temporal Entity

P118

overlaps in time with (is overlapped in time by)

E2 Temporal Entity

E2 Temporal Entity

P119

meets in time with (is met in time by)

E2 Temporal Entity

E2 Temporal Entity

P120

occurs  before (occurs  after)

E2 Temporal Entity

E2 Temporal Entity

P121

overlaps with

E53 Place

E53 Place

P122

borders with

E53 Place

E53 Place

P125

used object of type (was type of object used in)

E7 Activity

E55 Type

P32

   -   used general technique (was technique of)

E7 Activity

E55 Type

P126

employed (was employed in)

E11 Modification

E57 Material

P127

has broader term (has narrower term)

E55 Type

E55 Type

P128

carries (is carried by)

E24 Physical Man-Made Thing

E73 Information Object

P65

   -   shows visual item (is shown by)

E24 Physical Man-Made Thing

E36 Visual Item

P130

shows features of (features are also found on)

E70 Thing

E70 Thing

P73

   -   has translation (is translation of)

E33 Linguistic Object

E33 Linguistic Object

P132

overlaps with

E4 Period

E4 Period

P133

is separated from

E4 Period

E4 Period

P139

has alternative form

E41 Appellation

E41 Appellation

P140

assigned attribute to (was attributed by)

E13 Attribute Assignment

E1 CRM Entity

P34

   -   concerned (was assessed by)

E14 Condition Assessment

E18 Physical Thing

P39

   -   measured (was measured by)

E16 Measurement

E1 CRM Entity

P41

   -   classified (was classified by)

E17 Type Assignement

E1 CRM Entity

P141

assigned (was assigned by)

E13 Attribute Assignement

E1 CRM Entity

P35

   -   has identified (identified by)

E14 Condition Assessment

E3 Condition State

P37

   -   assigned (was assigned by)

E15 Identifier Assignement

E42 Identifier

P38

   -   deassigned (was deassigned by)

E15 Identifier Assignement

E42 Identifier

P40

   -   observed dimension (was observed in)

E16 Measurement

E54 Dimension

P42

   -   assigned (was assigned by)

E17 Type Assignment

E55 Type

P147

curated (was curated by)

E87 Curation Activity

E78 Collection

P148

has component (is component of)

E89 Propositional Object

E89 Propositional Object


CIDOC CRM Class Declarations

The classes of the CRM are comprehensively declared in this section using the following format:

 

·         Class names are presented as headings in bold face, preceded by the class’ unique identifier;

·         The line “Subclass of:” declares the superclass of the class from which it inherits properties;

·         The line “Superclass of:” is a cross-reference to the subclasses of this class;

·         The line “Scope note:” contains the textual definition of the concept the class represents;

·         The line “Examples:” contains a bulleted list of examples of instances of this class. If the example is also instance of a subclass of this class, the unique identifier of the subclass is added in parenthesis. If the example instantiates two classes, the unique identifiers of both classes is added in parenthesis. Non-fictitious examples may be followed by an explanation in brackets.

·         The line “Properties:” declares the list of the class’ properties;

·         Each property is represented by its unique identifier, its forward and reverse names, and the range class that it links to, separated by colons;

·         Inherited properties are not represented;

·         Properties of properties are provided indented and in parentheses beneath their respective domain property.

 


E1 CRM Entity

Superclass of:               E 2 Temporal Entity

E 5 2 Time-Span

E 5 3 Place

E 5 4 Dimension

E 7 7 Persistent Item

 

Scope note:               This class comprises all things in the universe of discourse of the CIDOC Conceptual Reference Model.

 

It is an abstract concept providing for three general properties:

1.       Identification by name or appellation, and in particular by a preferred identifier

2.       Classification by type, allowing further refinement of the specific subclass an instance belongs to

3.       Attachment of free text for the expression of anything not captured by formal properties

 

With the exception of E59 Primitive Value, all other classes within the CRM are directly or indirectly specialisations of E1 CRM Entity.

 

Examples:

§         the earthquake in Lisbon 1755 (E5)

 

Properties:

P1 is identified by (identifies): E41 Appellation

P2 has type (is type of): E55 Type

P 3 has note: E62 String

              (P3.1 has type: E55 Type)

P4 8 has preferred identifier (is preferred identifier of): E 4 2 Identifier

P137 exemplifies (is exemplified by): E55 Type

E2 Temporal Entity

Subclass of:                 Ε 1 CRM Entity

Superclass of:               Ε 3 Condition State

                                    E4 Period

 

Scope note:               This class comprises all phenomena, such as the instances of E4 Periods, E5 Events and states, which happen over a limited extent in time.

 

              In some contexts, these are also called perdurants. This class is disjoint from E77 Persistent Item. This is an abstract class and has no direct instances. E2 Temporal Entity is specialized into E4 Period, which applies to a particular geographic area (defined with a greater or lesser degree of precision), and E3 Condition State, which applies to instances of E18 Physical Thing.

Examples:

§         Bronze Age (E4)

§         the earthquake in Lisbon 1755 (E5)

§         the Peterhof Palace near Saint Petersburg being in ruins from 1944 – 1946 (E3)

Properties:

P4 has time-span (is time-span of): E52 Time-Span

P114 is equal in time to: E2 Temporal Entity

P115 finishes (is finished by): E2 Temporal Entity

P116 starts (is started by): E2 Temporal Entity

P117 occurs during (includes): E2 Temporal Entity

P118 overlaps in time with (is overlapped in time by): E2 Temporal Entity

P119 meets in time with (is met in time by): E2 Temporal Entity

P120 occurs before (occurs after): E2 Temporal Entity

E3 Condition State

Subclass of:                 E 2 Temporal Entity

 

Scope note:               This class comprises the states of objects characterised by a certain condition over a time-span.

 

An instance of this class describes the prevailing physical condition of any material object or feature during a specific E52 Time Span. In general, the time-span for which a certain condition can be asserted may be shorter than the real time-span, for which this condition held.

The nature of that condition can be described using P2 has type . For example, the E3 Condition State “condition of the SS Great Britain between 22 September 1846 and 27 August 1847” can be characterized as E55 Type “wrecked”.

 

Examples:

§         the “ Amber Room ” in Tsarskoje Selo being completely reconstructed from summer 2003 until now

§         the Peterhof Palace near Saint Petersburg being in ruins from 1944 – 1946

§         the state of my turkey in the oven at 14:30 on 25 December, 2002 ( P2 has type: E55 Type “still not cooked”)

Properties:

P5 consists of (forms part of): E3 Condition State

E4 Period

Subclass of:                 E2 Temporal Entity

Superclass of:               E 5 Event

 

Scope note:                             This class comprises sets of coherent phenomena or cultural manifestations bounded in time and space.

 

It is the social or physical coherence of these phenomena that identify an E4 Period and not the associated spatio-temporal bounds. These bounds are a mere approximation of the actual process of growth, spread and retreat. Consequently, different periods can overlap and coexist in time and space, such as when a nomadic culture exists in the same area as a sedentary culture.

 

Typically this class is used to describe prehistoric or historic periods such as the “Neolithic Period”, the “Ming Dynasty” or the “McCarthy Era”. There are however no assumptions about the scale of the associated phenomena. In particular all events are seen as synthetic processes consisting of coherent phenomena. Therefore E4 Period is a superclass of E5 Event. For example, a modern clinical E67 Birth can be seen as both an atomic E5 Event and as an E4 Period that consists of multiple activities performed by multiple instances of E39 Actor.

 

There are two different conceptualisations of ‘artistic style’, defined either by physical features or by historical context. For example, “Impressionism” can be viewed as a period lasting from approximately 1870 to 1905 during which paintings with particular characteristics were produced by a group of artists that included (among others) Monet, Renoir, Pissarro, Sisley and Degas. Alternatively, it can be regarded as a style applicable to all paintings sharing the characteristics of the works produced by the Impressionist painters, regardless of historical context. The first interpretation is an E4 Period, and the second defines morphological object types that fall under E55 Type.

 

Another specific case of an E4 Period is the set of activities and phenomena associated with a settlement, such as the populated period of Nineveh .

 

Examples:

§         Jurassic

§         European Bronze Age

§         Italian Renaissance

§         Thirty Years War

§         Sturm und Drang

§         Cubism

Properties:

P7 took place at (witnessed): E53 Place

P8 took place on or within (witnessed): E19 Physical Object

P9 consists of (forms part of): E4 Period

P10 falls within (contains): E4 Period

P132 overlaps with: E4 Period

P133 is separated from: E4 Period

E5 Event

Subclass of:                 E4 Period

Superclass of:               E7 Activity

E 6 3 Beginning of Existence

E6 4 End of Existence

 

Scope note:               This class comprises changes of states in cultural, social or physical systems, regardless of scale, brought about by a series or group of coherent physical, cultural, technological or legal phenomena. Such changes of state will affect instances of E77 Persistent Item or its subclasses.

 

The distinction between an E5 Event and an E4 Period is partly a question of the scale of observation. Viewed at a coarse level of detail, an E5 Event is an ‘instantaneous’ change of state. At a fine level, the E5 Event can be analysed into its component phenomena within a space and time frame, and as such can be seen as an E4 Period. The reverse is not necessarily the case: not all instances of E4 Period give rise to a noteworthy change of state.

Examples:

§         the birth of Cleopatra (E67)

§         the destruction of Herculaneum by volcanic eruption in 79 AD (E6)

§         World War II (E7)

§         the Battle of Stalingrad (E7)

§         the Yalta Conference (E7)

§         my birthday celebration 28-6-1995 (E7)

§         the falling of a tile from my roof last Sunday

§         the CIDOC Conference 2003 (E7)

Properties:

P11 had participant (participated in): E39 Actor

P12 occurred in the presence of (was present at): E77 Persistent Item

E6 Destruction

Subclass of:                 E64 End of Existence

 

Scope note:               This class comprises events that destroy one or more instances of E18 Physical Thing such that they lose their identity as the subjects of documentation. 

 

Some destruction events are intentional, while others are independent of human activity. Intentional destruction may be documented by classifying the event as both an E6 Destruction and E7 Activity.

 

The decision to document an object as destroyed, transformed or modified is context sensitive:

1.  If the matter remaining from the destruction is not documented, the event is modelled solely as E6 Destruction.

2. An event should also be documented using E81 Transformation if it results in the destruction of one or more objects and the simultaneous production of others using parts or material from the original. In this case, the new items have separate identities. Matter is preserved, but identity is not.

3. When the initial identity of the changed instance of E18 Physical Thing is preserved, the event should be documented as E11 Modification.

Examples:

§         the destruction of Herculaneum by volcanic eruption in 79 AD

§         the destruction of Nineveh (E6, E7)

§         the breaking of a champagne glass yesterday by my dog

Properties:

P13 destroyed (was destroyed by): E18 Physical Thing

E7 Activity

Subclass of:                 E 5 Event

Superclass of:               E8 Acquisition

E9 Move

E10 Transfer of Custody

E 1 1 Modification

E1 3 Attribute Assignment

E65 Creation

E66 Formation

E85 Joining

E86 Leaving

E87 Curation Activity

 

Scope note:               This class comprises actions intentionally carried out by instances of E39 Actor that result in changes of state in the cultural, social, or physical systems documented.

 

This notion includes complex, composite and long-lasting actions such as the building of a settlement or a war, as well as simple, short-lived actions such as the opening of a door.

Examples:

§           the Battle of Stalingrad

§           the Yalta Conference

§           my birthday celebration 28-6-1995

§           the writing of “Faust” by Goethe (E65)

§           the formation of the Bauhaus 1919 (E66)

§           calling the place identified by TGN ‘7017998’ ‘Quyunjig’ by the people of Iraq

Properties:

P14 carried out by (performed): E39 Actor

(P14.1 in the role of: E55 Type)

P15 was influenced by (influenced): E1 CRM Entity

P16 used specific object (was used for): E70 Thing

(P16.1 mode of use: E55 Type)

P17 was motivated by (motivated): E1 CRM Entity

P19 was intended use of (was made for): E71 Man-Made Thing

(P19.1 mode of use: E55 Type)

P20 had specific purpose (was purpose of): E5 Event

P2 1 had general purpose (was purpose of): E55 Type

P32 used general technique (was technique of): E55 Type

P33 used specific technique (was used by): E29 Design or Procedure

P125 used object of type (was type of object used in): E55 Type

P134 continued (was continued by): E7 Activity

 

E8 Acquisition

Subclass of:                 E7 Activity

 

Scope note:               This class comprises transfers of legal ownership from one or more instances of E39 Actor to one or more other instances of E39 Actor.

 

The class also applies to the establishment or loss of ownership of instances of E18 Physical Thing. It does not, however, imply changes of any other kinds of right. The recording of the donor and/or recipient is optional. It is possible that in an instance of E8 Acquisition there is either no donor or no recipient. Depending on the circumstances, it may describe:

 

1.       the beginning of ownership

2.       the end of ownership

3.       the transfer of ownership

4.       the acquisition from an unknown source

5.       the loss of title due to destruction of the item

 

It may also describe events where a collector appropriates legal title, for example by annexation or field collection. The interpretation of the museum notion of "accession" differs between institutions. The CRM therefore models legal ownership (E8 Acquisition) and physical custody (E10 Transfer of Custody) separately. Institutions will then model their specific notions of accession and deaccession as combinations of these.

Examples

§           the collection of a hammer-head shark of the genus Sphyrna (Carchariniformes) XXXtbc by John Steinbeck and Edward Ricketts at Puerto Escondido in the Gulf of Mexico on March 25th, 1940

§           the acquisition of El Greco’s painting entitled ‘The Apostles Peter and Paul’ by the State Hermitage in Saint Petersburg

§           the loss of my stuffed chaffinch ‘Fringilla coelebs Linnaeus, 1758’ due to insect damage last year

Properties:

P22 transferred title to (acquired title through): E39 Actor

P23 transferred title from (surrendered title through): E39 Actor

P24 transferred title of (changed ownership through): E18 Physical Thing

E9 Move

Subclass of:                 E7 Activity

 

Scope note:               This class comprises changes of the physical location of the instances of E19 Physical Object.

 

Note, that the class E9 Move inherits the property P7 took place at (witnessed): E53 Place . This property should be used to describe the trajectory or a larger area within which a move takes place, whereas the properties P26 moved to (was destination of) , P27 moved from (was origin of) describe the start and end points only. Moves may also be documented to consist of other moves (via P9 consists of (forms part of) ), in order to describe intermediate stages on a trajectory. In that case, start and end points of the partial moves should match appropriately between each other and with the overall event.

Examples

§         the relocation of London Bridge from the UK to the USA

§         the movement of the exhibition “Treasures of Tut-Ankh-Amun ” 1976-1979

Properties:

P25 moved (moved by): E19 Physical Object

P26 moved to (was destination of): E53 Place

P27 moved from (was origin of): E53 Place

E10 Transfer of Custody

Subclass of:                 E7 Activity

 

Scope note:               This class comprises transfers of physical custody of objects between instances of E39 Actor.

 

The recording of the donor and/or recipient is optional. It is possible that in an instance of E10 Transfer of Custody there is either no donor or no recipient. Depending on the circumstances it may describe:

1.       the beginning of custody

2.       the end of custody

3.       the transfer of custody

4.       the receipt of custody from an unknown source

5.       the declared loss of an object

 

The distinction between the legal responsibility for custody and the actual physical possession of the object should be expressed using the property P2 has type (is type of) . A specific case of transfer of custody is theft.

 

The interpretation of the museum notion of "accession" differs between institutions. The CRM therefore models legal ownership and physical custody separately. Institutions will then model their specific notions of accession and deaccession as combinations of these.

Examples:

§         the delivery of the paintings by Secure Deliveries Inc. to the National Gallery

§         the return of Picasso’s “ Guernica ” to Madrid ’s Prado in 1981

Properties:

P28 custody surrendered by (surrendered custody through): E39 Actor

P29 custody received by (received custody through): E39 Actor

P30 transferred custody of (custody transferred through): E18 Physical Thing

E11 Modification

Subclass of:                 E 7 Activity

Superclass of:               E12 Production

                            E79 Part Addition

                            E80 Part Removal

 

Scope note:               This class comprises all instances of E7 Activity that create, alter or change E24 Physical Man-Made Thing.

 

This class includes the production of an item from raw materials, and other so far undocumented objects, and the preventive treatment or restoration of an object for conservation.

 

Since the distinction between modification and production is not always clear, modification is regarded as the more generally applicable concept. This implies that some items may be consumed or destroyed in a Modification, and that others may be produced as a result of it. An event should also be documented using E81 Transformation if it results in the destruction of one or more objects and the simultaneous production of others using parts or material from the originals. In this case, the new items have separate identities.

 

If the instance of the E29 Design or Procedure utilised for the modification prescribes the use of specific materials, they should be documented using properties of the design or procedure, rather than via P126 employed (was employed in): E57 Material .

Examples:

§         the construction of the SS Great Britain (E12)

§         the impregnation of the Vasa warship in Stockholm for preservation after 1956

§         the transformation of the Enola Gay into a museum exhibit by the National Air and Space Museum in Washington DC between 1993 and 1995 (E12, E81)

§         the last renewal of the gold coating of the Toshogu shrine in Nikko , Japan

Properties:

P31 has modified (was modified by): E24 Physical Man-Made Thing

P126 employed (was employed in): E57 Material

E12 Production

Subclass of:                 E11 Modification

                            E63 Beginning of Existence

 

Scope note:               This class comprises activities that are designed to, and succeed in, creating one or more new items.

 

It specializes the notion of modification into production. The decision as to whether or not an object is regarded as new is context sensitive. Normally, items are considered “new” if there is no obvious overall similarity between them and the consumed items and material used in their production. In other cases, an item is considered “new” because it becomes relevant to documentation by a modification. For example, the scribbling of a name on a potsherd may make it a voting token. The original potsherd may not be worth documenting, in contrast to the inscribed one.

 

This entity can be collective: the printing of a thousand books, for example, would normally be considered a single event.

 

An event should also be documented using E81 Transformation if it results in the destruction of one or more objects and the simultaneous production of others using parts or material from the originals. In this case, the new items have separate identities and matter is preserved, but identity is not.

Examples:

§         the construction of the SS Great Britain

§         the first casting of the Little Mermaid from the harbour of Copenhagen

§         Rembrandt’s creating of the seventh state of his etching “Woman sitting half dressed beside a stove”, 1658, identified by Bartsch Number 197 (E12,E65,E81)

Properties:

P108 has produced (was produced by): E24 Physical Man-Made Thing

E13 Attribute Assignment

Subclass of:                 E 7 Activity

Superclass of:               E14 Condition Assessment

E15 Identifier Assignment

E16 Measurement

E17 Type Assignment

 

Scope note:               This class comprises the actions of making assertions about properties of an object or any relation between two items or concepts.

 

This class allows the documentation of how the respective assignment came about, and whose opinion it was. All the attributes or properties assigned in such an action can also be seen as directly attached to the respective item or concept, possibly as a collection of contradictory values. All cases of properties in this model that are also described indirectly through an action are characterised as "short cuts" of this action. This redundant modelling of two alternative views is preferred because many implementations may have good reasons to model either the action or the short cut, and the relation between both alternatives can be captured by simple rules.

 

In particular, the class describes the actions of people making propositions and statements during certain museum procedures, e.g. the person and date when a condition statement was made, an identifier was assigned, the museum object was measured, etc. Which kinds of such assignments and statements need to be documented explicitly in structures of a schema rather than free text, depends on if this information should be accessible by structured queries.

Examples:

§           the assessment of the current ownership of Martin Doerr’s silver cup in February 1997

Properties:

P140 assigned attribute to (was attributed by): E1 CRM Entity

P141 assigned (was assigned by): E1 CRM Entity

E14 Condition Assessment

Subclass of:                 E13 Attribute Assignment

 

Scope note:               This class describes the act of assessing the state of preservation of an object during a particular period.

 

The condition assessment may be carried out by inspection, measurement or through historical research. This class is used to document circumstances of the respective assessment that may be relevant to interpret its quality at a later stage, or to continue research on related documents.

 

Examples:

·         last year’s inspection of humidity damage to the frescos in the St. George chapel in our village

Properties:

P34 concerned (was assessed by): E18 Physical Thing

P35 has identified (identified by): E3 Condition State

E15 Identifier Assignment

Subclass of:                 E13 Attribute Assignment

 

Scope note:               This class comprises activities that result in the allocation of an identifier to an instance of E1 CRM Entity. An E15 Identifier Assignment may include the creation of the identifier from multiple constituents, which themselves may be instances of E41 Appellation. The syntax and kinds of constituents to be used may be declared in a rule constituting an instance of E29 Design or Procedure.

 

Examples of such identifiers include Find Numbers, Inventory Numbers, uniform titles in the sense of librarianship and Digital Object Identifiers (DOI). Documenting the act of identifier assignment and deassignment is especially useful when objects change custody or the identification system of an organization is changed. In order to keep track of the identity of things in such cases, it is important to document by whom, when and for what purpose an identifier is assigned to an item.

 

The fact that an identifier is a preferred one for an organisation can be expressed by using the property E1 CRM Entity. P48 has preferred identifier (is preferred identifier of): E42 Identifier . It can better be expressed in a context independent form by assigning a suitable E55 Type, such as “preferred identifier assignment”, to the respective instance of E15 Identifier Assignment via the P2 has type property.

Examples:

§           Replacement of the inventory number TA959a by GE34604 for a 17 th century lament cloth at the Museum Benaki, Athens

§                     Assigning the author-uniform title heading “Goethe, Johann Wolfgang von, 1749-1832. Faust. 1. Theil.” for a work (E28)

§                     On June 1, 2001 assigning the personal name heading “Guillaume, de Machaut, ca. 1300-1377” (E42,E82) to Guillaume de Machaut (E21)

Properties:

P37 assigned (was assigned by): E42 Identifier

P38 deassigned (was deassigned by): E42 Identifier

P142 used constituent (was used in): E41 Appellation

E16 Measurement

Subclass of:                 E13 Attribute Assignment

 

Scope note:               This class comprises actions measuring physical properties and other values that can be determined by a systematic procedure.

 

Examples include measuring the monetary value of a collection of coins or the running time of a specific video cassette.

 

The E16 Measurement may use simple counting or tools, such as yardsticks or radiation detection devices. The interest is in the method and care applied, so that the reliability of the result may be judged at a later stage, or research continued on the associated documents. The date of the event is important for dimensions, which may change value over time, such as the length of an object subject to shrinkage. Details of methods and devices are best handled as free text, whereas basic techniques such as "carbon 14 dating" should be encoded using P2 has type (is type of:) E55 Type .

Examples:

§           measurement of height of silver cup 232 on the 31 st   August 1997

§           the carbon 14 dating of the “Schoeninger Speer II” in 1996 [an about 400.000 years old Palaeolithic complete wooden spear found in Schoeningen, Niedersachsen, Germany in 1995]

Properties:

P39 measured (was measured by): E70 Thing

P 4 0 observed dimension (was observed in): E54 Dimension

E17 Type Assignment

Subclass of:                 E13 Attribute Assignment

 

Scope note:               This class comprises the actions of classifying items of whatever kind. Such items include objects, specimens, people, actions and concepts.

 

This class allows for the documentation of the context of classification acts in cases where the value of the classification depends on the personal opinion of the classifier, and the date that the classification was made. This class also encompasses the notion of "determination," i.e. the systematic and molecular identification of a specimen in biology.

Examples:

§           the first classification of object GE34604 as Lament Cloth, October 2 nd

§           the determination of a cactus in Martin Doerr’s garden as ‘ Cereus hildmannianus K.Schumann’, July 2003

Properties:

P 4 1 classified (was classified by): E1 CRM Entity

P4 2 assigned (was assigned by): E55 Type

E18 Physical Thing

Subclass of:                 E 7 2 Legal Object

Superclass of:               E 1 9 Physical Object

E24 Physical Man-Made Thing

E26 Physical Feature

 

Scope Note:               This class comprises all persistent physical items with a relatively stable form, man-made or natural.

 

Depending on the existence of natural boundaries of such things, the CRM distinguishes the instances of E19 Physical Object from instances of E26 Physical Feature, such as holes, rivers, pieces of land etc. Most instances of E19 Physical Object can be moved (if not too heavy), whereas features are integral to the surrounding matter.

 

The CRM is generally not concerned with amounts of matter in fluid or gaseous states.

Examples:

§           the Cullinan Diamond (E19)