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arXiv · 1805.07642

On testing substitutability

Cosmina Croitoru·Kurt Mehlhorn
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Abstract

The papers~\cite{hatfimmokomi11} and~\cite{azizbrilharr13} propose algorithms for testing whether the choice function induced by a (strict) preference list of length $N$ over a universe $U$ is substitutable. The running time of these algorithms is $O(|U|^3\cdot N^3)$, respectively $O(|U|^2\cdot N^3)$. In this note we present an algorithm with running time $O(|U|^2\cdot N^2)$. Note that $N$ may be exponential in the size $|U|$ of the universe.

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Cosmina Croitoru, Kurt Mehlhorn. 2018-05-19. On testing substitutability. https://arxiv.org/abs/1805.07642

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