Look up packages flexmix and mclust! Christian
On Thu, 21 May 2009, daniele riggi wrote:
Hi, I would like to know if it is possible to have a "R code" to estimate the parameters of a mixture of bivariate (or multivariate) normals via EM Algorithm. I tried to write it, but in the estimation of the matrix of variance and covariance, i have some problems. I generate two bidimensional vectors both from different distribution with their own vector means and variance and covariance structure. When I create a unique vector, the structure of covariance changes, and so the implementation of the EM algorithm doesn't work. Maybe someone knows the reason. If I fix the starting initial value of the covariance matrix and I don't update the estimate of this matrix, the algorithm works and finds the estimate of the vector means, so I wrote it in the correct way. However if someone could help me I will be very grateful to him for kindness. Best RegardsDaniele -- Dr. Daniele Riggi, PhD student University of Milano-Bicocca Department of Statistics Building U7, Via Bicocca degli Arcimboldi, 8 20126 Milano, Italy cell. +39 328 3380690 mailto: daniele.ri...@gmail.com [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
*** --- *** Christian Hennig University College London, Department of Statistical Science Gower St., London WC1E 6BT, phone +44 207 679 1698 chr...@stats.ucl.ac.uk, www.homepages.ucl.ac.uk/~ucakche ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.