Hi Otis
thanks, so the scores are relative to the result set.
Unfortunately I only have access to an xmlwebservice that let me send a
lucene query so I don't have access to the various IndexSearcher
methods. So it sounds like rather than just taking the top result and
using that Ill have to take the first 10 results and work out my own
score based on how many fields match and the importance of each field,
unless anyone has any other ideas ?
Otis Gospodnetic wrote:
Paul,
That is because the Hits class is likely being used under the covers. When you
use the IndexSearcher's search(...) method that returns Hits, hit scores are
normalized, so they are always between 0 and 1. If you want the raw scores,
and it sounds like you do, you could use a lower-level search method, like the
one that uses a HitCollector.
Otis
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Simpy -- http://www.simpy.com/ - Tag - Search - Share
----- Original Message ----
From: Paul Taylor <[EMAIL PROTECTED]>
To: java-user@lucene.apache.org
Sent: Wednesday, May 2, 2007 10:30:12 AM
Subject: Problem with scoring:is it absolute or relative ?
Hi I am having problems understanding lucenes scoring. I am using the
Musicbrainz which uses Lucene to provide searching facility over its
data, which put simply consists of a database about recording artists ,
albums and song titles
I can construct a query such as:
track:Minus AND artist:beck AND release:odelay
to return Tracks called Minus by the Artist Beck for the release Odelay,
which works fine if all terms are correct however I am trying to
implement the search in a program which takes the terms from values
embedded in existing audio files, so they may not be correct, so instead
of using an AND search I want to use a OR search such as
track:Minus artist:beck release:odelay
to improve the chances of getting a match, and then using the scoring
returned work out whether the match is sufficiently simailr to accept it
as a match.
Now the good news is that when multiple results are returned the record
with the top score is normally the best match BUT the bad news is that
if the match is very poor the top rated records normally return a score
of 100 even though
only a few of the terms match.
track:Minus artist:rubbish release:odelay
will return the Minus tracks by beck for the release odelay even through
the artist term is incorrect because this is the best match it can make
(2 out of 3 terms matched) but it is returning a score of 100 when I
would expect a score
of 66 because only two of the terms match.
Why is it doing this, and how can I create a query that only returns 100
if all terms match but will return possible matches where only some
terms match ? I have spoke to the creators of MusicBrainz they say they
are not using any kind of document/Field boosting and are that sure how
its work as theve only added lucene to the site quite recently.
The above queries can be run tested from
http://musicbrainz.org/search.html
by:
entering the query in the 'Search For' box
selecting type:Track
selecting Use advanced query syntax
<http://musicbrainz.org/popup/TextSearchSyntax>
and clicking on Indexed Search
thanks Paul Taylor
---------------------------------------------------------------------
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]
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
