copying user group - I keep replying directly vs reply all :) On Wed, Nov 26, 2014 at 2:03 PM, Nick Pentreath <nick.pentre...@gmail.com> wrote:
> ALS will be guaranteed to decrease the squared error (therefore RMSE) in > each iteration, on the *training* set. > > This does not hold for the *test* set / cross validation. You would > expect the test set RMSE to stabilise as iterations increase, since the > algorithm converges - but not necessarily to decrease. > > On Wed, Nov 26, 2014 at 1:57 PM, Kostas Kloudas <kklou...@gmail.com> > wrote: > >> Hi all, >> >> I am getting familiarized with Mllib and a thing I noticed is that >> running the MovieLensALS >> example on the movieLens dataset for increasing number of iterations does >> not decrease the >> rmse. >> >> The results for 0.6% training set and 0.4% test are below. For training >> set to 0.8%, the results >> are almost identical. Shouldn’t it be normal to see a decreasing error? >> Especially going from 1 to 5 iterations. >> >> Running 1 iterations >> Test RMSE for 1 iter. = 1.2452964343277886 (52.757125927000004 s). >> Running 5 iterations >> Test RMSE for 5 iter. = 1.3258973764470259 (61.183927666 s). >> Running 9 iterations >> Test RMSE for 9 iter. = 1.3260308117704385 (61.84948875800001 s). >> Running 13 iterations >> Test RMSE for 13 iter. = 1.3260310099809915 (73.799510125 s). >> Running 17 iterations >> Test RMSE for 17 iter. = 1.3260310102735398 (77.56512185300001 s). >> Running 21 iterations >> Test RMSE for 21 iter. = 1.3260310102739703 (79.607495074 s). >> Running 25 iterations >> Test RMSE for 25 iter. = 1.326031010273971 (88.631776301 s). >> Running 29 iterations >> Test RMSE for 29 iter. = 1.3260310102739712 (101.178383079 s). >> >> Thanks a lot, >> Kostas >> --------------------------------------------------------------------- >> To unsubscribe, e-mail: user-unsubscr...@spark.apache.org >> For additional commands, e-mail: user-h...@spark.apache.org >> >> >
