I think it is not possible, by only modifying Similarity, to make the total
score only count for documents boosts (which is the original request in
this discussion).
This is because a higher level scorer always sums the scores of "its"
sub-scorers - is this right...? if so there are probably two options:
- using Solr's FunctionQuery as suggested earlier in this thread,
maintaining the desired score in a dedicated field rather than in doc boost
- this is perhaps a better approach, because the doc boost was not intended
for this use (it only resides in 1 byte together with other factors, etc.)
- writing a dedicated (top level) scorer - and query, and weight - that
would not sum on subscorers.
Chris Hostetter <[EMAIL PROTECTED]> wrote on 13/09/2006 11:06:20:
>
> 1) This is not java. Since it's not java, i can't even begin to guess
> what odd excentricities might exist in whatever lucene port you are
> using.
> 2) If this *were* java then it wouldn't work th way you want it to, since
> you have the tf function returning "1" regardless of the frequency ...
> this method needs to return "0" sometimes, otherwise *everything* is a
> match
I agree that tf='always 1' is weird on scoring computations, but since tf
is checked only for documents that contain the processed term (walking
termDocs), actually tf would never return 0. An idf='always 1' seems to me
more harsh for the scoring process - if it is this way modified, it should
be set a much smaller value.
> 3) based on #2, and the resulst you describe i'm guessing your similarity
> isn't being used at all -- check that, add a System.out.println("BOO")
> (or whatever the correlary is in this langauge) to all ofthese
methods, i
> don't think you'll ever see that output -- start with figuring out why
> your similarity is being used before you try to fix it any more.
> 4) once you are sure your Similarity is being used, then take a look at
> the IndexSearcher.explain methods --they are your best riend in
> tweaking scoring information.
>
>
> : Date: Wed, 13 Sep 2006 14:42:13 +0200
> : From: Marcus Falck <[EMAIL PROTECTED]>
> : Reply-To: java-user@lucene.apache.org
> : To: java-user@lucene.apache.org
> : Subject: SV: SV: Changing the Scoring api
> :
> : It didn't really work for booleanqueries either. I thought it was
> working for some hours but to my big disappointment I realized that
> this was not the case.
> :
> : Im using two IndexReaders ( RAM and FS ) and one multireader.
> Creating one indexsearcher by passing the multireader as
constructorargument.
> :
> : Set the similarity class to my own similarity class using the
> SetSimilarity method on the searcher.
> :
> : This is the source for the similarity class I'm using:
> :
> : public class BoostOnlySimilarity : Similarity
> : {
> : /// <summary>Implemented as
<code>1/sqrt(numTerms)</code>.</summary>
> : public override float LengthNorm(System.String fieldName,
> int numTerms)
> : {
> : return 1;
> : }
> :
> : /// <summary>Implemented as
> <code>1/sqrt(sumOfSquaredWeights)</code>. </summary>
> : public override float QueryNorm(float sumOfSquaredWeights)
> : {
> : // Deal with the multiple terms issue
> : return 1;
> : //return (float)(1.0 / sumOfSquaredWeights); // return 1;
> : }
> :
> : /// <summary>Implemented as <code>sqrt(freq)</code>. </summary>
> : public override float Tf(float freq)
> : {
> : return 1;
> : }
> :
> : /// <summary>Implemented as <code>1 / (distance + 1)
> </code>. </summary>
> : public override float SloppyFreq(int distance)
> : {
> : return 1;
> : }
> :
> : public override float Idf(Lucene.Net.Index.Term term,
> Searcher searcher)
> : {
> : return 1;
> : }
> : public override float Ldf(int docFreq, int numDocs)
> : {
> : return 1;
> : }
> : /// <summary>Implemented as <code>overlap /
> maxOverlap</code>. </summary>
> : public override float Coord(int overlap, int maxOverlap)
> : {
> : return 1;
> : }
> :
> : }
> :
> :
> : /
> : Marcus
> :
> :
> : -----Ursprungligt meddelande-----
> : Från: Chris Hostetter [mailto:[EMAIL PROTECTED]
> : Skickat: den 12 september 2006 17:20
> : Till: java-user@lucene.apache.org
> : Ämne: Re: SV: Changing the Scoring api
> :
> :
> : : However the BooleanQuery's disableCoord seems to make effect.
> : : But I still have the problem when I'm constructing queries with
wildcards.
> :
> : really? ... that's strange, WildcardQuery uses the disableCoord feature
of
> : BooleanQuery. Do you have an example of what you mean?
> :
> : : already had implemented my own similarity class that has the coord
fixed
> : : to 1. And it doesn't work as excepted.
> :
> : are you setting your Similarity as the default on your IndexSearcher
prior
> : to executing your Queries?
> :
> :
> : -Hoss
> :
> :
> : ---------------------------------------------------------------------
> : To unsubscribe, e-mail: [EMAIL PROTECTED]
> : For additional commands, e-mail: [EMAIL PROTECTED]
> :
> :
> :
> :
> : ---------------------------------------------------------------------
> : To unsubscribe, e-mail: [EMAIL PROTECTED]
> : For additional commands, e-mail: [EMAIL PROTECTED]
> :
>
>
>
> -Hoss
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [EMAIL PROTECTED]
> For additional commands, e-mail: [EMAIL PROTECTED]
>
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
