Near-critical bipartite configuration models and their associated intersection graphs

Abstract: Recently, van der Hofstad, Komj\'{a}thy, and Vadon (2022) identified the critical point for the emergence of a giant connected component for the bipartite configuration model (BCM) and used this to analyze its associated random intersection graph (RIG) (2021). We extend some of this analysis to understand the graph at, and near, criticality. In particular, we show that under certain moment conditions on the empirical degree distributions, the number of vertices in each connected component listed in decreasing order of their size converges, after appropriate re-normalization, to the excursion lengths of a certain thinned L\'{e}vy process. Our approach allows us to obtain the asymptotic triangle counts in the RIG built from the BCM. Our limits agree with the limits recently identified by Wang (2023) for the RIG built from the bipartite Erd\H{o}s-R\'{e}nyi random graph.