Last meeting we discussed quite generally about ontologies and other KR technologies, so this time we decided to start looking more meticulously into the details of a widely known ontology for the cultural heritage domain, the CIDOC-CMR conceptual model (an ISO standard since 2006).

Doerr. The CIDOC conceptual reference module: an ontological approach to semantic interoperability of metadata. AI Magazine archive (2003) vol. 24 (3) pp. 75-92

The CIDOC-CRM is the de facto standard for data integration in the museum community. Its authors claim that it “is intended to be a common language for domain experts and implementers to formulate requirements for information systems and to serve as a guide for good practice of conceptual modelling. In this way, it can provide the “semantic glue” needed to mediate between different sources of cultural heritage information, such as that published by museums, libraries and archives”.

CIDOC contains a wealth of inspiring ideas and useful approaches; in our first meeting about it we highlighted only a few of them, including:

Here are some slides including key passages from the CIDOC paper mentioned above:

Information objects

One thing that CIDOC doesn’t cover much is the domain of information objects, which is a fancy term ontologists use to refer to anything that can carry information, such as a book, a stone inscription, or a piece of music. Modeling this type of entities using a clear (and possibly formal) language may seem straightforward at first: a book is a simple physical object, isn’t it?

However this is not always the case: things easily get muddled as soon as you start thinking about the fact that a book can have multiple copies, that it can be translated into many languages, or it can be included into a different edition. In all these cases, what is the ‘book’ entity we’re talking about? Not the physical object, apparently.

How to model information objects is a topic that librarians (among others) have discussed quite extensively in the years. As a result of these discussion librarians developed a conceptual model called FRBR, which has become a standard to follow when dealing with this type of problems.

FRBR (represented schematically above) summarizes quite well various important features of information objects, especially when considered under the perspective many library scientists have. However it is also true that FRBR doesn’t present its results using the rigourous and unambiguous language of formal ontologies. As a result, people end up interpreting the meaning of its concepts in slightly different ways. For example, if you are a librarian with little knowledge of computer science, you might end up using FRBR in a totally different way than that of a computer scientist who’d designing a software system for librarians.

To address this limitation, and also in order to open up the CIDOC-CRM model to the librarian community, the CIDOC committee has started ‘ontologizing’ FRBR. The second part of our seminar focused on this (ongoing) enterprise, which is outlined in this article:

Bekiari, C., Doerr, M., & Boeuf, P. L. (2009). FRBR: Object-Oriented Definition and Mapping to FRBR-ER (version 1.0). International Working Group on FRBR and CIDOC CRM Harmonisation.

Here are the slides I used in the seminar, which contain some of the most salient visual representation of the ontology:

That’s all for now – in the future we’ll be looking at specific situations where using CIDOC and FRBR presents challenges to the digital humanist: stay tuned!

In this tutorial Mizoguchi talks about representation – represented-thing – representational-form etc.. No mention of information-objects, which are instead (only as a term, maybe) always present everywhere else (Dolce, Cidoc, Cyc). So what’s the proper mapping? Is an IO a representation? Moreover, I am trying to put also another model in the picture, FRBR. This bibliographic standard focuses around concepts such as work, expression and manifestation, mainly. So how do these come into the game?

Sometimes I end up in some sort of ontological relativism. Since the objects we study are essentially multidimensional, and since we humans can only rationally perceive a portion of such dimensions at a given time, it follows that whatever perspective we decide to take on our objects of investigation, it will be fundamentally arbitrary and partial. In other words, there is no chance of having a single unifying perspective on reality, one which can contain all the others. No chance. So every representation gives you one side of the story only – which can be related to other sides, but never in its entirety.
If this is the case, we better keep all the possible ‘sides’ of this story, and just use the one we need whenever we need it. A pragmatist approach? Well.. more on this to come soon! (i’d also like to go back to Peirce, and check how all of this relates to his work)

Back to us: this is the model used in Dolce (more precisely, in the DnS module of Dolce, as described in Gangemi, A., Borgo, S., & Catenacci, C. (2005). Metokis deliverable D07 – Task Taxonomies for Knowledge Content. Deliverable of the EU FP6 project Metokis):

And this is an example of its instantiation:

The theory of Mizoguchi, as I said, it’s quite different. Here’s an interesting excerpt from the article Mizoguchi, R. (2004). Tutorial on ontological engineering – Part 3: Advanced course of ontological engineering. New Generation Computing, 22(2), 198–220.

A representation is composed of two parts, form and content.

Representation
…….p/o “form”: Representational form
…….p/o”content”: Proposition

where p/o stands for part-of relation/slot, “form” slot name and “: Representation” is a class constraint the slot value has to satisfy. Its identity is inherited from the form which is usually what people sense its existence. On the other hand, the content is the hidden part and it is a proposition which the author of the representation would like to convey through the representation.
[…]
It is critical to distinguish among proposition(content), representation and form of representation. In fact, although a novel is written in terms of sentences, novel is not a subclass of representation. What exists as a subclass of representation are what have the form of representation as its intrinsic property, that is, sentence, musical score, painting, etc. The sentences of Tale of Genji are instance-of sentence. However, representation and form of representation are different. Concerning a novel, representation is “sentence” which is composed of its content(novel) and “natural language” which is the syntactic part of the sentence, as the form of representation.

This is a quite impressive visual rendering of this ontological theory:

How are these theories different from each other? What are their pros and cons, where is it that they could be used more successfully? There’s work to be done here..