Catch up on stories from the past week (and beyond) at the Slashdot story archive


Forgot your password?
Get HideMyAss! VPN, PC Mag's Top 10 VPNs of 2016 for 55% off for a Limited Time ×
Programming Technology

Collaborative Filtering and the Rise of Ensembles 58

igrigorik writes "First the Netflix challenge was won with the help of ensemble techniques, and now the GitHub challenge is over, and more than half of the top entries are also based on ensembles. Good knowledge of statistics, psychology and algorithms is still crucial, but the ensemble technique alone has the potential to make the collaborative filtering space a lot more, well, collaborative! Here's a look at the basic theory behind ensembles, how they shaped the results of the GitHub challenge, and how this pattern can be used in the future."
This discussion has been archived. No new comments can be posted.

Collaborative Filtering and Rise of Ensembles

Comments Filter:
  • by reginaldo ( 1412879 ) on Tuesday September 01, 2009 @03:19PM (#29277101)
    One of the difficulties of ensemble development is weighting the logic that is being develeped. For instance, one of the problems we deal with at my job is matching incoming text to it's cleaned value. We have a list of approved words ['happy', 'sad', 'angry', 'sleepy'], and a text input of 'hap'. We need to determine which valid word 'hap' should match. Some rules I can think of for properly matching are:

    1.)Length of input compared to cleaned word.
    2.)Number of nonpositional letter matches.
    3.)Number of positional letter matches.

    Depending on how rules are weighted determines what the answer will be (either sad or happy). I know at my job this weighting process requires very careful politicking. :D

As in certain cults it is possible to kill a process if you know its true name. -- Ken Thompson and Dennis M. Ritchie