The PREMIS Editorial Committee has been discussing whether and how to allow the description of an Intellectual Entity in the PREMIS Data Dictionary.    Currently a PREMIS Object can link to an Intellectual Entity but you can not use PREMIS semantic units to describe the Intellectual Entity.

PREMIS defines Intellectual Entity as "a set of content that is considered a single intellectual unit for purposes of management and description: for example, a particular book, map, photograph, or database. An Intellectual Entity can include other Intellectual Entities; for example, a Web site can include a Web page; a Web page can include an image. An Intellectual Entity may have one or more digital representations."

The EC has had several requests to consider expanding the Data Dictionary to include description of Intellectual Entities.  We identified a number of use cases for doing this, although not all cases are equally strong.

1) A repository may want to represent an Intellectual Entity in order to capture descriptive metadata for it, have business requirements associated with it, show relationships, give high level rights information, or record related events and/or agents.

2) The repository may want to represent a batch of files with similar properties (e.g. environments) in order to avoid repetition of this information.  The files would not consitute a representation. 

3) The repository is sending a copy of an archived AIP containing multiple representations to another repository (for example, using the TIPR Repository Exchange Format) and wants to describe the package as a whole, as distinct from each representation.

4) The repository may want to describe a complex event such as a web craw.

5) The repository may want to distinguish intellectual file properties from actual file properties.

6) The repository may want to capture versioning information at the Intellectual Entity level for IE's such as articles or issues.

The EC's modeling showed that the most satisfying way of including Intellectual Entity in the Data Dictionary was to treat it as a fourth type of Object entity, along with Representations, Files and Bitstreams.  The advantages to this approach are:

Analysis has shown that nearly all of the semantic units applicable to Representations also seem applicable to Intellectual Entities.  Of course, this changes the Data Model and requires a major revision of the Data Dictionary.  Version 2.1 of the Data Dictionary is coming out very soon, and will not include any change to Intellectual Entity.  If we did add Intellectual Entity as a fourth Object type, it would probably be issued some time in the future as Version 3.0.

Before finalizing such a change, we would like to hear any comments the community of PREMIS implementers may have.  Do you see use cases for describing Intellectual Entity in PREMIS?  Are you comfortable with defining a new type of Object Entity?  Do you see semantic units that apply to Representations that do not apply to Intellectual Entities?  Are there additional semantic units that would pertain to Intellectual Entities that would be useful to include in the Data Dictionary?

If you have comments, please send them to the PIG list ([log in to unmask]) so we can get some open discussion going on this.