## The Annals of Statistics

### Fixed points of the EM algorithm and nonnegative rank boundaries

#### Abstract

Mixtures of $r$ independent distributions for two discrete random variables can be represented by matrices of nonnegative rank $r$. Likelihood inference for the model of such joint distributions leads to problems in real algebraic geometry that are addressed here for the first time. We characterize the set of fixed points of the Expectation–Maximization algorithm, and we study the boundary of the space of matrices with nonnegative rank at most $3$. Both of these sets correspond to algebraic varieties with many irreducible components.

#### Article information

Source
Ann. Statist., Volume 43, Number 1 (2015), 422-461.

Dates
First available in Project Euclid: 6 February 2015

https://projecteuclid.org/euclid.aos/1423230085

Digital Object Identifier
doi:10.1214/14-AOS1282

Mathematical Reviews number (MathSciNet)
MR3311865

Zentralblatt MATH identifier
1308.62035

#### Citation

Kubjas, Kaie; Robeva, Elina; Sturmfels, Bernd. Fixed points of the EM algorithm and nonnegative rank boundaries. Ann. Statist. 43 (2015), no. 1, 422--461. doi:10.1214/14-AOS1282. https://projecteuclid.org/euclid.aos/1423230085

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