lucene-java-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Cedric Ho" <cedric...@gmail.com>
Subject Re: Can I do boosting based on term postions?
Date Thu, 02 Aug 2007 02:07:09 GMT
Thanks for the quick response =)

On 8/1/07, Shailendra Sharma <shailendra.sharma@gmail.com> wrote:
> Yes, it is easily doable through "Payload" facility. During indexing process
> (mainly tokenization), you need to push this extra information in each
> token. And then you can use BoostingTermQuery for using Payload value to
> include Payload in the score. You also need to implement Similarity for this
> (mainly scorePayload method).

If I store, say a custom boost factor as Payload, does it means that I
will store one more byte per term per document in the index file? So
the index file would be much larger?

>
> Other way can be to extend SpanTermQuery, this already calculates the
> position of match. You just need to do something to use this position value
> in the score calculation.

I see that SpanTermQuery takes a TermPositions from the indexReader
and I can get the term position from there. However I am not sure how
to incorporate it into the score calculation. Would you mind give a
little more detail on this?

>
> One possible advantage of SpanTermQuery approach is that you can play
> around, without re-creating indices everytime.
>
> Thanks,
> Shailendra Sharma,
> CTO, Ver se' Innovation Pvt. Ltd.
> Bangalore, India
>
> On 8/1/07, Cedric Ho <cedric.ho@gmail.com> wrote:
> >
> > Hi all,
> >
> > I was wondering if it is possible to do boosting by search terms'
> > position in the document.
> >
> > for example:
> > search terms appear in the first 100 words, or first 10% words, or in
> > first two paragraphs would be given higher score.
> >
> > Is it achievable through using the new Payload function in lucene 2.2?
> > Or are there any easier ways to achieve these ?
> >
> >
> > Regards,
> > Cedric
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
> > For additional commands, e-mail: java-user-help@lucene.apache.org
> >
> >
>

Thanks,
Cedric

---------------------------------------------------------------------
To unsubscribe, e-mail: java-user-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-user-help@lucene.apache.org


Mime
View raw message