Re: Positive log-likelihood with Gaussian mixture

2018-05-30 Thread Simon Dirmeier
I see, thanks for clearning that up. I was aware of the fact for uniform distributions, but not for normal ones. So that would mean, some of the components have such a small variance that the loglik is positive in the end? Cheers, Simon Am 30.05.18 um 11:22 schrieb robin.e...@xense.co.uk:

Re: Positive log-likelihood with Gaussian mixture

2018-05-30 Thread robin . east
Positive log likelihoods for continuous distributions are not unusual. You are evaluating a pdf not a probability. For example a univariate Gaussian pdf returns greater than 1 at the mean when the variance goes below 0.39, at which point the log pdf is positive. Sent from Polymail (

Re: Positive log-likelihood with Gaussian mixture

2018-05-29 Thread Simon Dirmeier
Hey, sorry for the late reply. I cannot share the data but the problem can be reproduced easily, like below. I wanted to check with sklearn and observe a similar behaviour, i.e. a positive per-sample average log-likelihood

Positive log-likelihood with Gaussian mixture

2018-05-24 Thread Simon Dirmeier
Dear all, I am fitting a very trivial GMM with 2-10 components on 100 samples and 5 features in pyspark and observe some of the log-likelihoods being positive (see below). I don't undestand how this is possible. Is this a bug or an intended behaviour? Furthermore, for different seeds,