Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-31 Thread bthirion
> Hi, > > Thanks for this - yes I think I see that now. (The values do indeed > differ by n_dim * n_samples * log(scale), but no 0.5 here.) > > I guess in a way the issue is that we typically evaluate point > likelihoods, rather than e.g. integrals within some bounds of certainty > of the measurem

Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-31 Thread Dan Stowell
On 31/10/12 16:09, bthirion wrote: > On 10/31/2012 04:50 PM, Dan Stowell wrote: >> Hi all, >> >> I'm still getting odd results using mixture.GMM depending on data >> scaling. In the following code example, I change the overall scaling but >> I do NOT change the relative scaling of the dimensions. Y

Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-31 Thread Martin Fergie
Hi Dan, I would have thought that it is the relative scaling that is important, not the overall scaling. I.e. each feature of your data set should have zero mean and unit variance. Martin On 31 October 2012 16:09, bthirion wrote: > On 10/31/2012 04:50 PM, Dan Stowell wrote: > > Hi all, > > >

Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-31 Thread bthirion
On 10/31/2012 04:50 PM, Dan Stowell wrote: > Hi all, > > I'm still getting odd results using mixture.GMM depending on data > scaling. In the following code example, I change the overall scaling but > I do NOT change the relative scaling of the dimensions. Yet under the > three different scaling set

Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-31 Thread Dan Stowell
Hi all, I'm still getting odd results using mixture.GMM depending on data scaling. In the following code example, I change the overall scaling but I do NOT change the relative scaling of the dimensions. Yet under the three different scaling settings I get completely different results:

Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-02 Thread Dan Stowell
On 02/10/12 13:58, Alexandre Passos wrote: > On Tue, Oct 2, 2012 at 7:48 AM, Dan Stowell > wrote: >> >> Hi all, >> >> I'm using the GMM class as part of a larger system, and something is >> misbehaving. Can someone confirm please: the results of using GMM.fit() >> shouldn't have a strong dependen

Re: [Scikit-learn-general] mixture.GMM and data ranges

2012-10-02 Thread Alexandre Passos
On Tue, Oct 2, 2012 at 7:48 AM, Dan Stowell wrote: > > Hi all, > > I'm using the GMM class as part of a larger system, and something is > misbehaving. Can someone confirm please: the results of using GMM.fit() > shouldn't have a strong dependence on the data ranges, should they? For > example, if

[Scikit-learn-general] mixture.GMM and data ranges

2012-10-02 Thread Dan Stowell
Hi all, I'm using the GMM class as part of a larger system, and something is misbehaving. Can someone confirm please: the results of using GMM.fit() shouldn't have a strong dependence on the data ranges, should they? For example, if one variable has a range 0-1000, while the other has a range