Grau2007history question 1 by lebo

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CSCI 6966 Advanced Semantic Web (Fall 2008)

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A Question from Tim Lebo about Grau2007history:

The authors open the abstract by stating, "The development of ontologies involves continuous but relatively small modifications." A reasonable first step to reduce the ontology development cycle is to tackle the problem addressed in the paper: classify ontology O^2 by reusing the "evidences" from the classification of O^1, the set of added axioms, and the set of removed axioms. Their "module" technique can then be applied at each committed change. This addresses the relatively small modifications aspect of ontology development,

1. but what about the continuous aspect?
2. Could "modules" be determined using a history longer than only the previous step?

Joshua Taylor 20080918 Presentation

Answer

Writes Joshua Taylor, There are probably a few aspects of this to examine.

• Given a contiguous sequence of versions of an ontology, if the Δ–O and Δ+O have been preserved for each (that is, what axioms are new, and what axioms are removed for each), then between any two versions in the sequence, it would be possible to create the (Δ–O,Δ+O) that would turn first ontology into the second. Then the technique described in the paper would be used as stated. Of course, the usefulness of this "incremental" change is going to decrease if the difference between ontology versions is significantly great, e.g., if there are no axioms in common between the two targeted versions.
• Were three versions of an ontology known, O1, O2, and O3, (versions corresponding to the affixed numerals), could anything special be done for O3 given the changes between O1 and O2, O2 and O3, and the synthesized changes between O1 and O3? I think that, perhaps, some advantage could be gained. For instance, if it were apparent that the net change from O1 to O3 was smaller than the change from O2 to O3, then modules and classification for O3 could be based on the O1–O3 differences.
• Were there multiple paths from an initial O1 to a final O3, say O1 ⇒ O2.a ⇒O3, and O1 ⇒ O2.b ⇒O3, some of the same optimizations could be used (e.g., determining whether O3 ought to be classified based on the changes from O1 through O2.a or O2.b).

I suspect that further use could be made of longer histories if we knew whether modules were necessarily minimal, since it might be possible to use modules from different ontologies in clever ways.

Tayloj 13:33, 18 September 2008 (UTC)