Or use a boost for the phrase, something like "beauty and the beast"^5
On Wed, Jan 31, 2018 at 8:43 AM, Walter Underwood <wun...@wunderwood.org> wrote: > You can use a separate field for title aliases. That is what I did for > Netflix search. > > Why disable idf? Disabling tf for titles can be a good idea, for example the > movie “New York, New York” is not twice as much about New York as some other > film that just lists it once. > > Also, consider using a popularity score as a boost. > > wunder > Walter Underwood > wun...@wunderwood.org > http://observer.wunderwood.org/ (my blog) > >> On Jan 31, 2018, at 4:38 AM, Sravan Kumar <sra...@caavo.com> wrote: >> >> Hi, >> We are using solr for our movie title search. >> >> >> As it is "title search", this should be treated different than the normal >> document search. >> Hence, we use a modified version of TFIDFSimilarity with the following >> changes. >> - disabled TF & IDF and will only have 1 as value. >> - disabled norms by specifying omitNorms as true for all the fields. >> >> There are 6 fields with different analyzers and we make use of different >> weights in edismax's qf & pf parameters to match tokens & boost phrases. >> >> But, movies could have aliases and have multiple titles. So, we made the >> fields multivalued. >> >> Now, consider the following four documents >> 1> "Beauty and the Beast" >> 2> "The Real Beauty and the Beast" >> 3> "Beauty and the Beast", "La bella y la bestia" >> 4> "Beauty and the Beast" >> >> Note: Document 3 has two titles in it. >> >> So, for a query "Beauty and the Beast" and with the above configuration all >> the documents receive same score. But 1,3,4 should have got same score and >> document 2 lesser than others. >> >> To solve this, we followed what is suggested in the following thread: >> http://lucene.472066.n3.nabble.com/Influencing-scores-on-values-in-multiValue-fields-td1791651.html >> >> Now, the fields which are used to boost are made to use Norms. And for >> matching norms are disabled. This is to make sure that exact & near exact >> matches are rewarded. >> >> But, for the same query, we get the following results. >> query: "Beauty & the Beast" >> Search Results: >> 1> "Beauty and the Beast" >> 4> "Beauty and the Beast" >> 2> "The Real Beauty and the Beast" >> 3> "Beauty and the Beast", "La bella y la bestia" >> >> Clearly, the changes have solved only a part of the problem. The document 3 >> should be ranked/scored higher than document 2. >> >> This is because lucene considers the total field length across all the >> values in a multivalued field for normalization. >> >> How do we handle this scenario and make sure that in multivalued fields the >> normalization is taken care of? >> >> >> -- >> Regards, >> Sravan >
