Accelerating EM: An Empirical Study

نویسندگان

  • Luis E. Ortiz
  • Leslie Pack Kaelbling
چکیده

Many applications require that we learn the pa­ rameters of a model from data. EM (E xpectation­ Maximization) is a method for learning the pa­ rameters of probabilistic models with missing or hidden data. There are instances in which this method is slow to converge. Therefore, sev­ eral accelerations have been proposed to improve the method. None of the proposed acceleration methods are theoretically dominant and experi­ mental comparisons are lacking. In this paper, we present the different proposed accelerations and compare them experimentally. From the re­ sults of the experiments, we argue that some acceleration of EM is always possible, but that which acceleration is superior depends on prop­ erties of the problem.

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تاریخ انتشار 1999