diff toolboxes/FullBNT-1.0.7/HMM/dhmm_em_demo.m @ 0:cc4b1211e677 tip

initial commit to HG from Changeset: 646 (e263d8a21543) added further path and more save "camirversion.m"
author Daniel Wolff
date Fri, 19 Aug 2016 13:07:06 +0200
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/HMM/dhmm_em_demo.m	Fri Aug 19 13:07:06 2016 +0200
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+O = 3;
+Q = 2;
+
+% "true" parameters
+prior0 = normalise(rand(Q,1));
+transmat0 = mk_stochastic(rand(Q,Q));
+obsmat0 = mk_stochastic(rand(Q,O));
+
+% training data
+T = 5;
+nex = 10;
+data = dhmm_sample(prior0, transmat0, obsmat0, T, nex);
+
+% initial guess of parameters
+prior1 = normalise(rand(Q,1));
+transmat1 = mk_stochastic(rand(Q,Q));
+obsmat1 = mk_stochastic(rand(Q,O));
+
+% improve guess of parameters using EM
+[LL, prior2, transmat2, obsmat2] = dhmm_em(data, prior1, transmat1, obsmat1, 'max_iter', 5);
+LL
+
+% use model to compute log likelihood
+loglik = dhmm_logprob(data, prior2, transmat2, obsmat2)
+% log lik is slightly different than LL(end), since it is computed after the final M step