Re: Thoughts and Questions on a e-Commerce Recommender System and Expired Items

2013-11-06 Thread Sigbjørn Dybdahl
Hi, Could this be due to a small number of items viewed/liked/purchased per user? Correct me if I'm wrong, but this would make the total recommendation space sparse, thus making it hard to find good recommendations (ie recommendations which are relevent and not obsolete). If so, it might be

Re: Thoughts and Questions on a e-Commerce Recommender System and Expired Items

2013-11-06 Thread Gokhan Capan
Cassio, I would implement a CandidateItemsStrategy that returns products that are available now. A neighborhood based recommender would iterate over those products, and rank them based on the similarity measure you provide. If the DataModel of your recommender does not contain most of your

Decaying score for old preferences when using the .refresh()

2013-11-06 Thread Cassio Melo
Assuming that most recent ratings or implicit preference data is more important than the older ones, I wonder if there is a way to decrease the importance (score) of old preference entries without having to update all previous preferences. Currently I'm fetching new preferences from time to time

Re: Thoughts and Questions on a e-Commerce Recommender System and Expired Items

2013-11-06 Thread Cassio Melo
Good idea Gokhan, thanks! @ Sigbjørn: Thanks for the feedback. In fact we have plenty of [implicit] preference data for each user, e.g. product view. What I found out is that data from a certain point in time were very noisy and inconsistent, when I started fetching from that point on I got much

Solr-recommender for Mahout 0.9

2013-11-06 Thread Pat Ferrel
Trying to integrate the Solr-recoemmender with the latest Mahout snapshot. The project uses a modified RecommenderJob because it needs SequenceFile output and to get the location of the preparePreferenceMatrix directory. If #1 and #2 are addressed I can remove the modified Mahout code from the

Re: Thoughts and Questions on a e-Commerce Recommender System and Expired Items

2013-11-06 Thread Pat Ferrel
If you have a lot of old historical data for products that no longer exist you may be getting recommendations from that set. Using the old data is, in principal fine and should make recs better. However you may be running into a limit for the default number of recs returned, which is something

Re: Solr-recommender for Mahout 0.9

2013-11-06 Thread Sebastian Schelter
Hi Pat, can you create issues for 1) and 2) ? Then I will try to get this into trunk asap. Best, Sebastian On 06.11.2013 19:13, Pat Ferrel wrote: Trying to integrate the Solr-recoemmender with the latest Mahout snapshot. The project uses a modified RecommenderJob because it needs

Re: Solr-recommender for Mahout 0.9

2013-11-06 Thread Pat Ferrel
Done, BTW I have the thing running on a demo site but am getting very poor results that I think are related to the Solr setup. I’d appreciate any ideas. The sample data has 27,000 items and something like 4000 users. The preference data is fairly dense since the users are professional