Chordal graphs are easily testable

Abstract

We prove that the class of chordal graphs is easily testable in the following sense. There exists a constant $c>0$ such that, if adding/removing at most $\epsilon n^2$ edges to a graph $G$ with $n$ vertices does not make it chordal, then a set of $(1/\epsilon)^c$ vertices of $G$ chosen uniformly at random induces a graph that is not chordal with probability at least $1/2$. This answers a question of Gishboliner and Shapira.