Ontological distance

[Carole Goble]

Semantic distance in ontologies is a hot topic. It differs between
ontologies that have asserted structure and those that have inferred (like
OWL).

I'm copying this message to two people to follow up (I'm ni a workshop
right now :-) )

a. Phil Lord who ahs developed semantic closeness measyres for the Gene
Ontology and has two papers on it

b. Sean Bechhofer who has done work on how to do semantic closeness in
inferred taxonomies and aslo has a paper on it.

Guys -- please point to thes epapers

Carole




> It strikes me that, in order to have an ontology-based system make
> suggestions about a given topic (of the type: also look at topic X), we
> need a concept of 'distance' between classes.
>
> Would it be possible to add a 'closeness' factor to a
> relationship-type. This factor would have values (for simplicity) of
> [positive, neutral, negative]. Any two classes tied by that
> relationship-type would be 'close' if the closeness factor of the
> relationship-type was positive and 'far away' if negative; if the
> factor was neutral, then nothing could be said about their closeness.
>
> Subsumption relationships ('is a type of', 'is a component of') would
> most likely be positive, while antonymic relationships ('is distinct
> from') would be negative relationships. Neutral relationships might be
> ??? (can't think of one :).
>
> A class would then be closest to other classes with which it had the
> greater number of relationships with 'positive' closeness over those
> with 'negative' closeness (eg distance to the class could be computed
> by number of positive relationships minus number of negative
> relationships).
>
> Is this reasonable? Has 'distance' been defined already? Is it feasible
> (eg with OilEdit and DAML+OIL, say)?
>
> Cheers,
> Tony.
>
> __
> Tony Linde                       Phone:  +44 (0)116 223 1292
> AstroGrid Project Manager        Fax:    +44 (0)116 252 3311
> Dept of Physics & Astronomy      Mobile: +44 (0)7753 603356
> University of Leicester          Email:  tol at star.le.ac.uk
> Leicester, UK   LE1 7RH          Web:    http://www.astrogrid.org
>