##### Simplifying Mixture Models with the Hierarchical EM Algorithm, and its Application to Eye Movement Analysis in Psychological Research

###### Antoni Chan and Janet Hsiao

###### City University of Hong Kong, University of Hong Kong

We propose a hierarchical EM algorithm for simplifying a finite mixture model into a reduced mixture model with fewer mixture components. The reduced model is obtained by maximizing a variational lower bound of the expected log-likelihood of a set of virtual samples. We develop three applications for our mixture