Re: Omitting tf but not positions

2011-02-25 Thread Jan Høydahl
I also have a case (yellow-page) where IDF comes in and destroys the rank. A company listing with a word which occurs in few other listings is not necessarily better than others just because of that. When it gets to the extreme value of IDF=1, we get an artificially high IDF boost. It is not

Re: Omitting tf but not positions

2011-02-25 Thread Robert Zotter
Jan, You are correct, you'll need your own Similarity class. Have a look at SweetSpotSimilarity (http://lucene.apache.org/java/3_0_3/api/contrib-misc/org/apache/lucene/misc/SweetSpotSimilarity.html) On 2/25/11 10:57 AM, Jan Høydahl wrote: I also have a case (yellow-page) where IDF comes in

Re: Omitting tf but not positions

2011-02-25 Thread Robert Muir
On Fri, Feb 25, 2011 at 1:57 PM, Jan Høydahl jan@cominvent.com wrote: I also have a case (yellow-page) where IDF comes in and destroys the rank. A company listing with a word which occurs in few other listings is not necessarily better than others just because of that. When it gets to the

Re: Omitting tf but not positions

2010-12-15 Thread Robert Muir
On Wed, Dec 15, 2010 at 3:09 AM, Jan Høydahl / Cominvent jan@cominvent.com wrote: Any way to disable TF/IDF normalization without also disabling positions? see Similarity.tf(float) and Similarity.tf(int) if you want to change this for both terms and phrases just override