What stochastic decomposition trick are you guys referring to? I appreciate if you could provide
some pointers.
________________________________
From: Jake Mannix <jake.mannix@gmail.com>
To: mahoutuser@lucene.apache.org
Cc: jnorstad@northwestern.edu
Sent: Tue, December 8, 2009 9:08:19 PM
Subject: Re: Fwd: A MapReduce Algorithm for Matrix Multiplication
On Tue, Dec 8, 2009 at 5:56 PM, Ted Dunning <ted.dunning@gmail.com> wrote:
> NMF should be amenable to the stochastic decomposition trick. That reduces
> the problem to a much smaller factorization that you could plausibly do
> using sequential techniques. Jake Mannix is working on getting
> factorizations going, but I don't know if he has gotten to NMF.
>
I'm not currently working on NMF, but the stochastic decomposition trick
will be
in there soon, which should allow all this pretty easily.
Although... if you start with a positive matrix, you may want a specialized
random
projector which preserves positivity for this kind of thing. But I'm not
sure, I
haven't looked too closely at what happens when you try to do this trick on
NMF.
jake
