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arXiv · 1007.1597

A Numerical Algorithm for Zero Counting. III: Randomization and Condition

Felipe Cucker·Teresa Krick·Gregorio Malajovich·Mario Wschebor
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Abstract

In a recent paper (Cucker, Krick, Malajovich and Wschebor, A Numerical Algorithm for Zero Counting. I: Complexity and accuracy, J. Compl.,24:582-605, 2008) we analyzed a numerical algorithm for computing the number of real zeros of a polynomial system. The analysis relied on a condition number kappa(f) for the input system f. In this paper, we look at kappa(f) as a random variable derived from imposing a probability measure on the space of polynomial systems and give bounds for both the tail P{kappa(f) > a} and the expected value E(log kappa(f)).

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Felipe Cucker, Teresa Krick, Gregorio Malajovich, Mario Wschebor. 2010-07-09. A Numerical Algorithm for Zero Counting. III: Randomization and Condition. https://doi.org/10.1016/j.aam.2011.07.001

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