lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Hoss Man (JIRA)" <>
Subject [jira] Commented: (LUCENE-1302) explain should not mask negative scores
Date Tue, 10 Jun 2008 17:10:45 GMT


Hoss Man commented on LUCENE-1302:

 minNrShouldMatch is all about matching, and  a match is a match is a match ... it doesn't
matter if the score is negative or not.  

if a sub query doesn't want to count as a match, it shouldn't match.

having the notion of a wrapper query like BQ that cares about a "minScore" from subqueries
in order for it to count a doc as a match would be something new.

> explain should not mask negative scores
> ---------------------------------------
>                 Key: LUCENE-1302
>                 URL:
>             Project: Lucene - Java
>          Issue Type: Bug
>          Components: Query/Scoring
>            Reporter: Doron Cohen
>            Assignee: Doron Cohen
>            Priority: Minor
>             Fix For: 2.4
>         Attachments: lucene-1302-explain-negative.patch
> Explanation.isMatch() returns false for 0 or negative scores. 
> Hence negative scores are omitted from the explanation.
> This causes, when using e.g. BoostingTermQuery with negative boosts, a difference between
the collected doc score and the score shown by explain().  
> A word on the usage of this - BTQ with negative boosts is useful for "punishing" documents
for containing a term. It also allows all sorts of tricks with multiplying query boost by
the BTQ boost, so you get a positive score if both boosts have the same sign but negative
otherwise. - I am sure there other uses as well.

This message is automatically generated by JIRA.
You can reply to this email to add a comment to the issue online.

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message