Hi, I'm currently integrating mahout's recommendation engine into a site.
I'm not quite clear what DataModel to use. PostgresJdbcDataModel looks handy, but seem to produce way to many queries. ReloadFromJDBCDataModel seems to address that problem but still needs to calculate the similarity of a given user to every other user in the system.
Would it be possible and performant to use lucene to perform the search for the top n most similar users, provided an index exists where the user id is the document id and the preferences of the users are the term vectors?
If that's possible, would it additionally be possible to use negative values in the term vector for recording dislikes of the user?
Best regards, Uwe
