Hi Kris, this sounds great, could you open a JIRA issue for that?
--sebastian On 01.05.2012 11:17, Kris Jack wrote: > Hello, > > I recently implemented a distributed user-based collaborative filtering > algorithm. I've tested it experimentally and found that it is better suited > to Mendeley's data set for generating recommendations than the item-based > implementation > (http://www.slideshare.net/KrisJack/mahout-becomes-a-researcher-large-scale-recommendations-at-mendeley). > > This is mostly because Mendeley's data set has far more items than users. > > I'd like to contribute this code to the Mahout project. This will be the > first patch that I write for Mahout so I'm following the instructions at > https://cwiki.apache.org/MAHOUT/how-to-contribute.html > > In brief, so far I've taken the code for the existing > org.apache.mahout.cf.taste.hadoop.item.RecommenderJob and created a new > org.apache.mahout.cf.taste.hadoop.user.RecommenderJob. With help from Sean > Owen, I followed a similar approach to the item-based implementation, but > multiplied a user-user matrix with a user-item vector rather than an > item-item matrix with an item-user vector. The result of the multiplication > then needs to be transposed in order to output recommendations by user id. > > Rather than changing the item-based code, I've created new classes for the > user-based version, which tend to be modified versions of the originals. It > would be much tidier to merge these together, where possible, and to > parametrise them. I didn't want to change the item-based code straight off, > however, without consulting you all. > > Would be great to get some feedback. > > Best, > Kris > > -- > View this message in context: > http://lucene.472066.n3.nabble.com/Distributed-User-based-Collaborative-Filtering-tp3952692.html > Sent from the Mahout Developer List mailing list archive at Nabble.com.
