[Xapian-discuss] Question about synonyms and relevancy results.

Olly Betts olly at survex.com
Thu Jan 3 17:21:55 GMT 2008


On Thu, Jan 03, 2008 at 04:18:15PM +0000, James Aylett wrote:
> I suppose in theory we could have an operator that acts as OP_OR but
> returns the highest BM25 termweight or something (so the synonyms act
> as an expansion inside the query, rather than outside as at the
> moment), but I have no idea if that would be generally useful, or
> practical with respect to any of the optimisations we do.

Richard is working on a new OP_SYNONYM operator on SVN branch opsynonym:

http://svn.xapian.org/branches/opsynonym/

See also:

http://www.xapian.org/cgi-bin/bugzilla/show_bug.cgi?id=50

OP_SYNONYM is like OP_OR except that the statistics are calculated as if
all the sub-postlists were postings of the same term (some
approximations are required to achieve this without the computations
being prohibitively expensive).

All being well this will be in 1.1.0.  

Cheers,
    Olly



More information about the Xapian-discuss mailing list