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arXiv · 2302.09692

Classification via Two-Way Comparisons

Marek Chrobak·Neal E. Young
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Abstract

Given a weighted, ordered query set $Q$ and a partition of $Q$ into classes, we study the problem of computing a minimum-cost decision tree that, given any query $q$ in $Q$, uses equality tests and less-than comparisons to determine the class to which $q$ belongs. Such a tree can be much smaller than a lookup table, and much faster and smaller than a conventional search tree. We give the first polynomial-time algorithm for the problem. The algorithm extends naturally to the setting where each query has multiple allowed classes.

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Marek Chrobak, Neal E. Young. 2023-02-19. Classification via Two-Way Comparisons. https://doi.org/10.1145/3709361

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