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Posted to java-user@lucene.apache.org by Michael Hartmann <mi...@web.de> on 2004/10/27 17:04:22 UTC
Boost value
Hello,
I am working on Lucene and tried to understand the calculation of the score
value. As far as I understand it works as follows:
(1) idf = ln(numDocs/(docFreq+1))
(2) queryWeight = idf * boost
(3) sumOfSquaredWeights = queryWeight * queryWeight
(4) norm = 1/sqrt(sumOfSquaredWeights)
------------------------------------------------
??? Question 1: why not
norm = 1/queryWeight
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(5) queryWeight' = queryWeight * norm
(6) weightValue = queryWeight' * idf
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??? Question 2: using (6) and insert (1) - (5) step by step
=> weightValue = idf
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I did only pure algebraical substitutions and it all comes to a simple
formula. The boost value is not needed anymore. Where is my fault?
Thanks,
Michael
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