1. ICS-FORTH September, 1999 1 The CIDOC CRM Format Martin Doerr Washington, Sept. 22, 1999 Foundation for Research and Technology - Hellas Institute of Computer Science Heraklion - Crete

2. ICS-FORTH September, 1999 2 The CIDOC CRM Definitions p “Entity” is called anything like: u “class”, “entity” “node”, “individual” u comparable to tables, but with meaning p “link” is called anything like: u “attribute”, “reference”, ”link”, “property”, “relation” u comparable to table-column, but with a role meaning p “Entity and its subclass” is anything like: u “isA”, “subclass - superclass”, “derived class - parent class”, “generalization - specialization”

3. ICS-FORTH September, 1999 3 The CIDOC CRM Links pLinks: u Optional (need not be instantiated) u Multivalued (e.g. “has author”!) u Strictly inherited (both sides !) u Can be specialized (see RDF:subproperty) u Can have links (to refine roles etc.) — can be implemented as entities if necessary...

4. ICS-FORTH September, 1999 4 The CIDOC CRM Implicit Metamodel p Entities are grouped by metaclasses ( “belongs to”) p Links are group by metacategories u like links between metacategories p The Metamodel serves as comment u But is formally correct u could be used to guide extensions of the model

5. ICS-FORTH September, 1999 5 The CIDOC CRM Naming Rules p Entities are named using initial capitals. p Entities are named using noun phrases (nominal group) p Links are named using lower case letters and are labeled in both directions. u Implementers can choose the appropriate part p Links are listed by priority at :Events, Objects, Actors,... p Links are named using verbal phrases, u states are named in present tense, u actions are named in past tense.

6. ICS-FORTH September, 1999 6 The CIDOC CRM Scope Notes p A statement that clarifies the meaning and usage an Entity or link: u Definition by properties, not linguistic!! u Definition of scope - bounds and distinctions for the model u Context of usage, purpose and implicit view u Illustration by examples uGuidance to similar, overlapping, associated concepts

7. ICS-FORTH September, 1999 7 The CIDOC CRM Format u Entity names (terms) are presented as headings in bold face, preceded by the arithmetic identifier. u The line “Belongs to:” refers to the metaclass, u The line “Subclass of:” declares the superclass of the entity, from which it inherits links u The line “Superclass of:” is a cross-reference to the following subclasses of this entity. u The line “Scope note” contains the textual definition of the concept the entity represents. u The title “Properties” announces the list of links. u Links are grouped by related meaning under metacategories, i.e. a series of titles as e.g. “classifications” etc., in normal face.

8. ICS-FORTH September, 1999 8 The CIDOC CRM Format uEach link is represented by its forward and backward name, and the entity it links to, separated by colon. uLinks declared directly for the entity are given in bold face. uInherited links are given in italics as cross-references to the respective superclasses for better comprehension. uInherited links with redefined (restricted ) target entity are given in bold face italics. uEach link may be followed by a scope note for the link in an indented text in smaller characters. uLinks of links are given in an indented position in parenthesis under the respective link.

9. ICS-FORTH September, 1999 9 The CIDOC CRM Format uThe title “The entity is referenced by:” announces the cross-reference list of links pointing to this entity. uEach cross-link is represented by the entity it originates from, and its forward and backward name, separated by colon, and in normal face. uThe title “The entity inherits references:” announces the cross-reference list of links pointing to any of the superclasses of this entity uEach inherited cross-link is represented by the entity it originates from, and its forward and backward name, separated by colon, and in italics.