On Aug 8, 2005, at 1:19 PM, Rajesh Munavalli wrote:
>> 2 How term weight is calculated in Lucene, how many types of term
>>
> weight calculating formulas are implemented and what are they?
> TFIDF weighting is used with some modifications to how the raw
> score is
> computed. You can refer to "Lucene In Action" by Otis Gospodnetic and
> Erik Hatcher" page 78. Here is the formula
>
> = SUMMATION {tf(t in d).idf(t).boost(t.field in d). lengthNorm
> (t.field
> in d)
> t in q
Note that the most crucial errata for Lucene in Action is on that
very formula. The corrected one is here:
http://www.lucenebook.com/blog/errata/scoring_formula_omission.html
Erik
