Sebastian/Sean, Thanks for your responses, first of I am more familiar with cross validation than grid search, regardless I'll go ahead and jira up tasks for building tools to support both grid search and training error checking. What about the clustering sub-section of the code, is there any cleanup/rearchitecture anticipated there ?
Sent from my iPhone On Jun 8, 2013, at 10:19 AM, Sean Owen <[email protected]> wrote: > PS you might find it useful to pinch a bit of this code to implement > convergence checking and grid search... not quite the same code base > but maps quite directly: > > https://code.google.com/p/myrrix-recommender/source/browse/trunk/online/src/net/myrrix/online/factorizer/als/AlternatingLeastSquares.java#226 > https://code.google.com/p/myrrix-recommender/source/browse/trunk/online/src/net/myrrix/online/eval/ParameterOptimizer.java#111 > > On Sat, Jun 8, 2013 at 6:05 PM, Sebastian Schelter <[email protected]> wrote: >> Hi Saikat, >> >> Great that you want to work on the ALS code. I think it is very >> important to make it easier to use, ideally no knowledge of the papers >> and formulas should be necessary. >> >> As you know, the ALS code has a hyperparameter lambda that needs to be >> tuned in order to get a good factorization. Are you familiar with grid >> search and cross validation? It would be awesome to add some tooling for >> them to Mahout that helps users to easily find a good lambda. >> >> Another important new feature would be to check the training error of >> the factorization during the computation to make it automatically detect >> convergence. Thereby users would not have to give the number of >> iterations to execute as parameter. >> >> What do you think, does this sound reasonable to you? >> >> Best, >> Sebastian >> >> >> On 08.06.2013 01:15, Saikat Kanjilal wrote: >>> Sebastien et al, >>> Per the latest comments on mahout-974 I'd like to get a deeper >>> understanding on what future improvements or architectural changes are >>> desired on the ALS subsection of the codebase. I'd love to help with the >>> development efforts on this codebase and on the clustering subsection as >>> well. >>> >>> Regards >>> >>> Sent from my iPhone >
