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arXiv · 2107.10640

Hash-Based Tree Similarity and Simplification in Genetic Programming for Symbolic Regression

Bogdan Burlacu·Lukas Kammerer·Michael Affenzeller·Gabriel Kronberger
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Abstract

We introduce in this paper a runtime-efficient tree hashing algorithm for the identification of isomorphic subtrees, with two important applications in genetic programming for symbolic regression: fast, online calculation of population diversity and algebraic simplification of symbolic expression trees. Based on this hashing approach, we propose a simple diversity-preservation mechanism with promising results on a collection of symbolic regression benchmark problems.

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Bogdan Burlacu, Lukas Kammerer, Michael Affenzeller, Gabriel Kronberger. 2021-07-22. Hash-Based Tree Similarity and Simplification in Genetic Programming for Symbolic Regression. https://doi.org/10.1007/2f978-3-030-45093-9_44

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