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arXiv · 2204.06461

Population Diversity Leads to Short Running Times of Lexicase Selection

Thomas Helmuth·Johannes Lengler·William La Cava
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Abstract

In this paper we investigate why the running time of lexicase parent selection is empirically much lower than its worst-case bound of O(N*C). We define a measure of population diversity and prove that high diversity leads to low running times O(N + C) of lexicase selection. We then show empirically that genetic programming populations evolved under lexicase selection are diverse for several program synthesis problems, and explore the resulting differences in running time bounds.

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Thomas Helmuth, Johannes Lengler, William La Cava. 2022-04-13. Population Diversity Leads to Short Running Times of Lexicase Selection. https://arxiv.org/abs/2204.06461

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