Re: PLSA

2014-07-07 Thread Denis Turdakov
Hi, Deb. Thanks for your idea to use ALS for PLSA training. I discussed it with our engineers and it seems it's better to use EM. We have the following points: 1. We have some doubts that ALS is applicable to the problem. By its definition, PLSA is a matrix decomposition with respect to Kullback–

Re: PLSA

2014-07-04 Thread Debasish Das
Thanks for the pointer... Looks like you are using EM algorithm for factorization which looks similar to multiplicative update rules Do you think using mllib ALS implicit feedback, you can scale the problem further ? We can handle L1, L2, equality and positivity constraints in ALS now...As long

Re: PLSA

2014-07-04 Thread Denis Turdakov
Hi, Deb. I don't quite understand the question. PLSA is an instance of matrix factorization problem. If you are asking about inference algorithm, we use EM-algorithm. Description of this approach is, for example, here: http://www.machinelearning.ru/wiki/images/1/1f/Voron14aist.pdf Best, Denis.

Re: PLSA

2014-07-03 Thread Debasish Das
Hi Denis, Are you using matrix factorization to generate the latent factors ? Thanks. Deb On Thu, Jul 3, 2014 at 8:49 AM, Denis Turdakov wrote: > Hello guys, > > We made pull request with PLSA and its modifications: > - https://github.com/apache/spark/pull/1269 > - JIRA issue SPARK-2199 > Co