[jira] [Reopened] (MAHOUT-676) Random samplers in a modular library

["Lance Norskog (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/MAHOUT-676?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Lance Norskog reopened MAHOUT-676:
----------------------------------


As mentioned, I got interested again.

> Random samplers in a modular library
> ------------------------------------
>
>                 Key: MAHOUT-676
>                 URL: https://issues.apache.org/jira/browse/MAHOUT-676
>             Project: Mahout
>          Issue Type: New Feature
>          Components: Math
>            Reporter: Lance Norskog
>            Priority: Minor
>         Attachments: MAHOUT-676.patch, Sampler.patch
>
>
> This is a modular suite of samplers. It supplies the ability to throw away samples in a useful way. 
> Here is a use case: for my recommendations, I want user activity to decide the amount of influence on the results. For the number of users who watch X number of movies: 1-5 is 20%, 6-15 is 50%, 15-30 is 30 %, and users who watch over 30 movies are not useful.
> * If I know the input distribution, I can supply a function to the Slice sampler to give this distribution. 
> * If I don't know the distribution, I can create a Reservoir sampler for each of the three buckets. After reading the whole set, I check the sizes of the various buckets and solve for my distribution. This gives the number of users to pull from each bucket.

--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira