Property Testing in Bounded Degree Hypergraphs
Hugo Aaronson, Gaia Carenini, Atreyi Chanda
TL;DR
This work generalizes the bounded-degree property-testing framework from graphs to $k$-uniform hypergraphs, and analyzes the sublinear query complexity for three core properties: colorability, $k$-partiteness, and independence number. It introduces a local, gap-preserving reduction $\ ho_{3\text{-col.}}$ from $(3,d)$-SAT to 3-uniform hypergraph colorability, using expander-based gadgets to enforce variable consistency and clause satisfaction, and proves $\ ilde{\Omega}(n)$-hardness for testing colorability and partiteness in bounded-degree hypergraphs. It further shows that while $k$-partiteness is maximally hard in general, it is strongly testable for hypergraphs with bounded treewidth, via a treewidth-preserving reduction to graph colorability. The paper also establishes hardness for testing independence number, and extends the lower bounds to two-sided testers while providing explicit hard instances through CSP-based constructions. These results highlight a sharp separation between dense and bounded-degree hypergraph models and extend the toolkit for sublinear hypergraph property testing.
Abstract
We extend the bounded degree graph model for property testing introduced by Goldreich and Ron (Algorithmica, 2002) to hypergraphs. In this framework, we analyse the query complexity of three fundamental hypergraph properties: colorability, $k$-partiteness, and independence number. We present a randomized algorithm for testing $k$-partiteness within families of $k$-uniform $n$-vertex hypergraphs of bounded treewidth whose query complexity does not depend on $n$. In addition, we prove optimal lower bounds of $Ω(n)$ on the query complexity of testing algorithms for $k$-colorability, $k$-partiteness, and independence number in $k$-uniform $n$-vertex hypergraphs of bounded degree. For each of these properties, we consider the problem of explicitly constructing $k$-uniform hypergraphs of bounded degree that differ in $Θ(n)$ hyperedges from any hypergraph satisfying the property, but where violations of the latter cannot be detected in any neighborhood of $o(n)$ vertices.
