Hi Robin, If you are asking why they are arrays, it is because to save clients from concatenating multiple matrices to create the input.
I am quoting from libFM paper<http://www.csie.ntu.edu.tw/~b97053/paper/Factorization%20Machines%20with%20libFM.pdf>: "For easier interpretation, the features are grouped into indicators for the active user (blue), active item (red), other movies rated by the same user (orange), the time in months (green), and the last movie rated (brown)." I thought a client would create multiple group of matrices, and he can just pass them all to the algorithm. Then the wModel is w parameters, it is still array of vectors for me to keep the indexing consistent, and vModel is the V parameters. Was that what you were asking? On Thu, Apr 11, 2013 at 6:44 PM, Robin Anil <robin.a...@gmail.com> wrote: > Comments away. I was a bit confused by the use of Vector[] for w1 and > Matrix[] for inputs. > > Robin Anil | Software Engineer | +1 312 869 2602 | Google Inc. > > > On Thu, Apr 11, 2013 at 10:00 AM, Gokhan Capan <gkhn...@gmail.com> wrote: > >> Ted, >> Robin, >> >> Although I did not test on a dataset yet, recently I've been implementing >> Factorization Machines with SGD optimization. >> >> The initial implementation is at https://github.com/gcapan/mahout/tree/fm >> >> Would you guys consider to take a look so I can make it better and >> running? >> >> >> >> On Mon, Apr 1, 2013 at 8:45 PM, Nkechi Nnadi <nkechi.nn...@gmail.com>wrote: >> >>> Hello, >>> >>> I'm long time lurker. I would be interested in implementing these. I >>> thought I would get my feet wet with contributing to wiki with tutorials >>> since I have used Mahout for recommendation and clustering in my >>> dissertation. I have never contributed code before and I would love to >>> start now. >>> >>> -Nkechi >>> >>> >>> On Sun, Mar 31, 2013 at 1:14 PM, Robin Anil <robin.a...@gmail.com> >>> wrote: >>> >>> > FMs work really well for a whole range of things. Having implemented >>> them >>> > myself, I can extend my services as a reviewer if anyone is willing to >>> > start on it. >>> > >>> > Robin Anil | Software Engineer | +1 312 869 2602 | Google Inc. >>> > >>> > >>> > On Sun, Mar 31, 2013 at 2:18 AM, Ted Dunning <ted.dunn...@gmail.com> >>> > wrote: >>> > >>> > > Relative to Dan's recent mention of SOM as possible new project, >>> here are >>> > > slides from KDD Cup 2012 in which Stephen Rendle describes how he did >>> > using >>> > > a very straightforward implementation of Factorization Machines >>> [1,2]. >>> > > >>> > > >>> > > FMs are interesting in the context of Mahout because they can be >>> used in >>> > a >>> > > wide variety of settings including recommendation and targeting and >>> > because >>> > > they have very good performance on a number of tasks. >>> > > >>> > > I should mention that Robin was the one who first mentioned FMs to >>> me. >>> > > >>> > > The KDD 2012 competition [3] is of interest in any case because it >>> > provides >>> > > a large amount of realistic data for commercially important problems. >>> > > >>> > > [1] >>> > > >>> > > >>> > >>> https://kaggle2.blob.core.windows.net/competitions/kddcup2012/2748/media/RendleSlides.pdf >>> > > >>> > > [2] >>> > > >>> > > >>> > >>> https://kaggle2.blob.core.windows.net/competitions/kddcup2012/2748/media/Rendle.pdf >>> > > >>> > > [3] http://www.kddcup2012.org/ >>> > > >>> > >>> >> >> >> >> -- >> Gokhan >> > > -- Gokhan
