On Sun, Dec 13, 2009 at 3:24 AM, Jake Mannix <[email protected]> wrote: > You do the co-occurrence matrix (for item-by-item, right?) on Hadoop too, > and that part is really fast, but computing the recommendations is very > slow? By what orders of magnitude, for the whole set? > > What are the scales you are testing with, in terms of total number of users, > items, and ratings?
Yes, for about 10M ratings (tens of thousands of users and items) the co-occurrence matrix counts take a couple minutes, and then recs are on track to take a day or two.
