Displaying 1 result from an estimated 1 matches for "wdf_upperbound_".
2013 Feb 19
2
Implementing tf-idf weighting scheme in Xapian
...urn 0 .
Moreover,an upper bound on W(t,d) for get_maxpart( ) can be found out
easily for a particular normalization (if I have all the required metrics
available).
For eg:- If I am using logarithmic normalization for the wdf (within
document frequency) ,then an upper bound on W(t,d) will be
(log(wdf_upperbound_)+1)*log(N/termfreq) as N(collection size) and
termfreq(number of documents indexed by the term t) will remain constant
for a given term t.
However,some normalizations for the wdf include the formula wdfn = wdf /
max(wdf,d) where max(wdf,d) is the maximum within document frequency of any
term in...