[ 
https://issues.apache.org/jira/browse/MAHOUT-1272?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13701241#comment-13701241
 ] 

Peng Cheng commented on MAHOUT-1272:
------------------------------------

The next step would be to create an online version of this (and recommender)
sgd is an online algorithm but now works only for batch recommender.
In the mean time the only online recommender in mahout is the slope-one, kind 
of a shame.
Will create a new JIRA ticket tomorrow.
                
> Parallel SGD matrix factorizer for SVDrecommender
> -------------------------------------------------
>
>                 Key: MAHOUT-1272
>                 URL: https://issues.apache.org/jira/browse/MAHOUT-1272
>             Project: Mahout
>          Issue Type: New Feature
>          Components: Collaborative Filtering
>            Reporter: Peng Cheng
>            Assignee: Sean Owen
>              Labels: features, patch, test
>         Attachments: mahout.patch, ParallelSGDFactorizer.java, 
> ParallelSGDFactorizerTest.java
>
>   Original Estimate: 336h
>  Remaining Estimate: 336h
>
> a parallel factorizer based on MAHOUT-1089 may achieve better performance on 
> multicore processor.
> existing code is single-thread and perhaps may still be outperformed by the 
> default ALS-WR.
> In addition, its hardcoded online-to-batch-conversion prevents it to be used 
> by an online recommender. An online SGD implementation may help build 
> high-performance online recommender as a replacement of the outdated 
> slope-one.
> The new factorizer can implement either DSGD 
> (http://www.mpi-inf.mpg.de/~rgemulla/publications/gemulla11dsgd.pdf) or 
> hogwild! (www.cs.wisc.edu/~brecht/papers/hogwildTR.pdf).
> Related discussion has been carried on for a while but remain inconclusive:
> http://web.archiveorange.com/archive/v/z6zxQUSahofuPKEzZkzl

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to