It takes the highest scoring document, if greater than 1.0, and divides every hit's score by this number, leaving them all <= 1.0. Actually, I just looked at the code, and it actually does this by taking 1/maxScore and then multiplying this by each score (equivalent results in the end, maybe more efficient(?)). See the method getMoreDocs() in Hits.java (org.apache.lucene.search.Hits):
[...] float scoreNorm = 1.0f; if (length > 0 && topDocs.getMaxScore() > 1.0f) { scoreNorm = 1.0f / topDocs.getMaxScore(); } int end = scoreDocs.length < length ? scoreDocs.length : length; for (int i = hitDocs.size(); i < end; i++) { hitDocs.addElement(new HitDoc(scoreDocs[i].score * scoreNorm, scoreDocs[i].doc)); } On 1/27/06, xing jiang <[EMAIL PROTECTED]> wrote: > Hi, > > I want to know how the lucene normalizes the score. I see hits class has > this function to get each document's score. But i dont know how lucene > calculates the normalized score and in the "Lucene in action", it only said > normalized score of the nth top scoring docuemnts. > -- > Regards > > Jiang Xing > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]