Hello, -> Have removed the member variable factor from all three schemes and renamed it in Init(). -> Have sorted out the problem of increasing bound in dph. Have removed the simplication of wdf * normalization and have restored it to wdf_upper * max_normalization. I tested it using cout in the code to identify the root of the problem. Regards Aarsh -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.xapian.org/pipermail/xapian-devel/attachments/20140612/f0c41c1d/attachment.html>