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arXiv · 1801.08751

Distances of optimal solutions of mixed-integer programs

Joseph Paat·Robert Weismantel·Stefan Weltge
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Abstract

A classic result of Cook et al. (1986) bounds the distances between optimal solutions of mixed-integer linear programs and optimal solutions of the corresponding linear relaxations. Their bound is given in terms of the number of variables and a parameter $ \Delta $, which quantifies sub-determinants of the underlying linear inequalities. We show that this distance can be bounded in terms of $ \Delta $ and the number of integer variables rather than the total number of variables. To this end, we make use of a result by Olson (1969) in additive combinatorics and demonstrate how it implies feasibility of certain mixed-integer linear programs. We conjecture that our bound can be improved to a function that only depends on $ \Delta $, in general.

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Joseph Paat, Robert Weismantel, Stefan Weltge. 2018-01-26. Distances of optimal solutions of mixed-integer programs. https://arxiv.org/abs/1801.08751

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