Regular pair of vertex sets
= Regular pair of vertex sets
= Regular pairs of vertex sets
{synonym}
= Regular pair
{synonym}
= Uniform pair
{synonym}
A pair $(A,B)$ is $\varepsilon$-regular when
$$
|d(X,Y)-d(A,B)|\leq\varepsilon
$$
whenever $X\subseteq A$, $Y\subseteq B$, $|X|\geq\varepsilon|A|$, and $|Y|\geq\varepsilon|B|$.