There’s been work done on the cross-recommender. There is a Mahout-style XRecommenderJob that has two preference models for two actions or preference types. It uses matrix multiply to get a cooccurrence type similarity matrix. If we had a cross-row-similarity-job, it could pretty easily be integrated and I’d volunteer to integrate it. The XRSJ is probably beyond me right now so if we can scare up someone to do that we’d be a long way down the road.
I’ll put a feature request into Jira and take this to the dev list BTW this is already integrated with the solr-recommender. On Feb 8, 2014, at 7:19 PM, Ted Dunning <ted.dunn...@gmail.com> wrote: I have different opinions about each piece. I think that cross recommendation is as core as RowSimilarityJob and should be a parallel implementation or integrated. Parallel is probably easier. It is even plausible to have a version of RowSimilarityJob that doesn't support all the different distance measures but does support multiple cross and direct processing using LLR or related cooccurrence based measures. It would be very cool if a single pass over the data could do many kinds of co or cross occurrence operations. For dithering, it really is post processing. That said, it is also the single largest improvement that anybody typically gets when testing different options so it is a bit goofy to not have good support for some kinds of dithering. For Thompson sampled recommenders, I am not sure where to start hacking on our current code. On Sat, Feb 8, 2014 at 4:53 PM, Pat Ferrel <p...@occamsmachete.com> wrote: > That was by no means to criticize effort level, which has been impressive > especially during the release. > > It was more a question about the best place to add these things and > whether they are important. Whether people see these things as custom post > processing or core. > > On Feb 8, 2014, at 12:13 PM, Ted Dunning <ted.dunn...@gmail.com> wrote: > > … > > The reason that we aren't adding this like cross-rec and other things is > that "we" have full-time jobs, mostly. Suneel is full-time on Mahout, but > the rest are not. You seem more active than most. > > >