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arXiv · 2605.18308

The edit distance of word-representable and comparability graphs

Sergey Kitaev·Ryan R. Martin
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Abstract

In this paper, we establish that the maximum edit distance of an $n$-vertex graph from the hereditary property of word-representable graphs is $n^2/8-o(n^2)$. In addition, we establish that the maximum edit distance of an $n$-vertex graph from the hereditary property of poset comparability graphs is $5n^2/32-o(n^2)$. In fact, we determine the edit distance function over all edge densities $p\in [0,1]$ for the property of word-representable graphs, for the property of $k$-word-representable graphs for each $k\geq 2$, and for the property comparability graphs. The latter has a peculiar structure that requires an infinite sequence of colored regularity graphs.

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Sergey Kitaev, Ryan R. Martin. 2026-05-18. The edit distance of word-representable and comparability graphs. https://arxiv.org/abs/2605.18308

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