Scores are only compatible if the query is the same, which is not the case for you. So you cannot merge hits from different queries.
----- Uwe Schindler H.-H.-Meier-Allee 63, D-28213 Bremen http://www.thetaphi.de eMail: u...@thetaphi.de > -----Original Message----- > From: Trejkaz [mailto:trej...@trypticon.org] > Sent: Wednesday, February 15, 2012 1:40 AM > To: Lucene Users Mailing List > Subject: Merging results from two searches on two separate Searchers > > Hi all. > > We have 1..N indexes for each time someone adds some data. Each time they > can choose different tokenisation settings. Because of this, each text index > has > its own query parser instance. Because each query parser could generate a > different Query (though I guess whether they do or not is another matter!) we > can't just use MultiReader and a single IndexSearcher. > > What we have been doing is performing the search against each index and then > merging the results by score. I remember from a long time ago that this was > not something you're supposed to do. > > Reading information I can find today, it sounds like the main problem was Hits > doing score normalisation. We cloned Hits a while back and inherited its score > normalisation code as well. > > So my questions: > - does normalising the scores do anything other than give people the > illusion > that scores are from 0.0 ~ 1.0? > - if I remove the score normalisation from our Hits-like class, is it now > totally > OK to merge the lists of results? > (And, I guess, if not, is there some trick I can employ to line the > scores for the > results up so that I can?) > > TX > > --------------------------------------------------------------------- > To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org > For additional commands, e-mail: java-user-h...@lucene.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: java-user-unsubscr...@lucene.apache.org For additional commands, e-mail: java-user-h...@lucene.apache.org
