Dear all, Why there is no Ranking function based on Probabilistic Retrieval Framework<http://en.wikipedia.org/wiki/Probabilistic_relevance_model> (ex.Okapi BM25) in Lucene. Actually there is third party implementation of the BM25 Model <http://nlp.uned.es/~jperezi/Lucene-BM25/> but it is no longer compatible with current release of Lucene.
*Why we are not planning to start implement in next release.* Please see this issue Thank you,
