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arXiv · 2610.27117

Subgraph probabilities in random intersection graphs

Katarzyna Rybarczyk·Grzegorz Serafin
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Abstract

Since their introduction by Karoński, Scheinerman, and Singer-Cohen in 90's, random intersection graphs have attracted much attention, mostly due to their various applications. In this article, we establish a general result for the probability that a given small subgraph is present in a random intersection graph. Our theorem applies to a broad range of parameters, including regimes that have not previously been considered in the literature. Moreover, it extends known results and situates them within a broader framework, making this approach a convenient tool for comparing the probabilities of graphs in the random intersection graph model. To prove our main result, we develop new proof techniques that, to the best of our knowledge, have not previously been employed in the study of small subgraphs in random intersection graphs. Many special cases and examples are presented as well.

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Katarzyna Rybarczyk, Grzegorz Serafin. 2026-10-19. Subgraph probabilities in random intersection graphs. https://arxiv.org/abs/2610.27117

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