HistoryMatters GregoryToddWilliams Question1

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• Question is for the Presentation: Joshua Taylor 20080918 Presentation
• Question is asked by: Gregory Todd Williams
• The Question is: The Gene Ontology seems to be the only ontology for which update sizes are varied during evaluation (with n=1,2,4) whereas the other ontologies are all tested for a fixed update size. Are the gains in reclassification time seen in the results expected to be the same across all ontologies, regardless of update size? Furthermore, is the seemingly narrow range of tested update sizes (1-4) expected to approximate real-world usage? Would the same gains be seen with updates of different characteristics such as unbalanced axiom removal/addition counts or larger updates (tens or hundreds of affected axioms)?

Answer

Writes Joshua Taylor, The sentence immediately preceding Table 7 says that "these results //suggest// that incremental classification time may grow linearly with the number of modified axioms; similar behavior can be observed for the remaining ontologies." I'd interpret this to mean that they observed similar effects with the other ontologies, though I agree that it's somewhat suspect that they didn't show any of those results.

With respect to how the number of changes affects reclassification time, number of modules affected, &c: Personally I suspect that randomly selected axioms to add or remove are likely to be involved with different concepts in the ontology. In actual practice, I imagine that a developer is as likely to modify axioms that are, in fact, related. I suspect that the changes in classification time are more dependent on the number of modules affected rather than the number of axioms. Only when the axioms to be changed are randomly selected are these likely to be directly proportional.

Tayloj 17:28, 17 September 2008 (UTC)