The EM Perspective of Directional Mean Shift Algorithm
- URL: http://arxiv.org/abs/2101.10058v1
- Date: Mon, 25 Jan 2021 13:17:12 GMT
- Title: The EM Perspective of Directional Mean Shift Algorithm
- Authors: Yikun Zhang, Yen-Chi Chen
- Abstract summary: The directional mean shift (DMS) algorithm is a nonparametric method for pursuing local modes of densities defined by kernel density estimators on the unit hypersphere.
We show that any DMS can be viewed as a generalized Expectation-Maximization (EM) algorithm.
- Score: 3.60425753550939
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: The directional mean shift (DMS) algorithm is a nonparametric method for
pursuing local modes of densities defined by kernel density estimators on the
unit hypersphere. In this paper, we show that any DMS iteration can be viewed
as a generalized Expectation-Maximization (EM) algorithm; in particular, when
the von Mises kernel is applied, it becomes an exact EM algorithm. Under the
(generalized) EM framework, we provide a new proof for the ascending property
of density estimates and demonstrate the global convergence of directional mean
shift sequences. Finally, we give a new insight into the linear convergence of
the DMS algorithm.
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