Are Okapi BM25 scores normalized into 0 and 1 ?

Can anybody provide me some information about it ? Even a small clue, I'm
kinda stuck on this and the owner of the libraries do not answer emails.

Thanks

Patrick if the question is about the code snippert at the page you mention, which I copy below, I believe the answer is no and the author is aware of it since he is adding a comment about not-normalized in the second example.

ScoreDocs and TopDocs are not returning normalized scores.
Normalized scores tend to be rare in Lucene nowadays, I believe earlier strategy was to divide by max-score when the latter was bigger than 1.

paul

IndexSearcher searcher = new IndexSearcher("IndexPath");

//Load average length
BM25Parameters.load(avgLengthPath);
BM25BooleanQuery query = new BM25BooleanQuery("This is my Query",
"Search-Field",
new StandardAnalyzer());

TopDocs top = searcher.search(query, null, 10);
ScoreDoc[] docs = top.scoreDocs;

//Print results
for (int i = 0; i $<$ top.scoreDocs.length; i++) {
System.out.println(docs[i].doc + ":"+docs[i].score);
}


Le 29 avr. 2011 à 13:20, Patrick Diviacco a écrit :

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