A macro-DAG structure based mixture model
نویسندگان
چکیده
In the context of unsupervised classification of multidimensional data, we revisit the classical mixture model in the case where the dependencies among the random variables are described by a DAG structure. The structure is considered at two levels, the original DAG and its macro-representation. This twolevel representation is the main base of the proposed mixture model. To perform unsupervised classification, we propose a dedicated algorithm called EM-mDAG, which extends the classical EM algorithm. In the Gaussian case, we show that this algorithm can be efficiently implemented. The experiments reveal that this method favors the selection of a small number of classes.
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