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arXiv · 1804.10936

Solving the likelihood equations to compute Euler obstruction functions

Jose Israel Rodriguez
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Abstract

Macpherson defined Chern-Schwartz-Macpherson (CSM) classes by introducing the (local) Euler obstruction function, which is an integer valued function on the variety that is constant on each stratum of a Whitney stratification of an algebraic variety. By understanding the Euler obstruction function, one gains insights about a singular algebraic variety. It was recently shown by the author and B. Wang, how to compute these functions using maximum likelihood degrees. This paper discusses a symbolic and a numerical implementation of algorithms to compute the Euler obstruction at a point. Macaulay2 and Bertini are used in the implementations.

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Jose Israel Rodriguez. 2018-04-29. Solving the likelihood equations to compute Euler obstruction functions. https://arxiv.org/abs/1804.10936

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