On Thu, Oct 18, 2012 at 06:59:22AM -0700, Phil Steitz wrote: > On 10/18/12 1:41 AM, Gilles Sadowski wrote: > > On Wed, Oct 17, 2012 at 10:26:55PM -0700, Phil Steitz wrote: > >> On 10/17/12 8:36 PM, Becksfort, Jared wrote: > >>> I see. I am planning to submit the EM fit for multivariate normal > >>> mixture models in the next couple of weeks (Math-817). A Gibbs sampling > >>> DP fit may be a bit further out. I am not opposed to allowing the > >>> number of components to change, but I also like the simplicity of this > >>> class. Whatever you guys decide is probably fine. > >> I like the interface as implemented for what it represents, > > By "interface", do you mean the class > > MixtureMultivariateRealDistribution" > > as implemented in the file on the JIRA page? > > Yes, the most recent one. I like the way you set up the > constructors, handling the weights and distribution type parameter. > > > >> but I > >> agree with Ted's point above. I also wonder if implementing the > >> multivariate distribution interface is really buying you anything. > >> Certainly not for the Gibbs sampler. It might be better to just > >> directly implement EM with an interface that is natural for fitting > >> and using mixture models. I am not sure this stuff belongs in the > >> distribution package in any case. > > As implemented, it seems quite natural. > > How this class will be used by non-existing code is beyond the scope of > > MATH-816. > > [And when the code exists, we can always revisit the design if necessary.] > > It works for fixed component models, which I guess is OK by > consensus to start. The question I was asking is what exactly do you > get by having it extend the multivariate real distribution?
Is it not a kind of distribution? [It's obvious that one can sample from it but maybe there are some required properties (for a distribution) which are missing from such a mixture (?).] > I guess > that will become clear when we get the EM implementation. Hopefully. > I am OK committing this, I just wanted to get a clearer picture of > how the class was going to be used. I wouldn't be able to answer. Gilles --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
