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arXiv · 2004.07735

Maximum likelihood degree, complete quadrics and ${\mathbb C}^*$-action

Mateusz Michałek·Leonid Monin·Jarosław Wiśniewski
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Abstract

We study the maximum likelihood (ML) degree of linear concentration models in algebraic statistics. We relate it to an intersection problem on the variety of complete quadrics. This allows us to provide an explicit, basic, albeit of high computational complexity, formula for the ML-degree. The variety of complete quadrics is an exact analog for symmetric matrices of the permutohedron variety for the diagonal matrices.

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Mateusz Michałek, Leonid Monin, Jarosław Wiśniewski. 2020-04-16. Maximum likelihood degree, complete quadrics and ${\mathbb C}^*$-action. https://arxiv.org/abs/2004.07735

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