{ "id": "2506.21543", "version": "v1", "published": "2025-06-26T17:58:22.000Z", "updated": "2025-06-26T17:58:22.000Z", "title": "Detecting weighted hidden cliques", "authors": [ "Urmisha Chatterjee", "Karissa Huang", "Ritabrata Karmakar", "B. R. Vinay Kumar", "Gábor Lugosi", "Nandan Malhotra", "Anirban Mandal", "Maruf Alam Tarafdar" ], "categories": [ "math.ST", "cs.IT", "math.IT", "math.PR", "stat.TH" ], "abstract": "We study a generalization of the classical hidden clique problem to graphs with real-valued edge weights. Formally, we define a hypothesis testing problem. Under the null hypothesis, edges of a complete graph on $n$ vertices are associated with independent and identically distributed edge weights from a distribution $P$. Under the alternate hypothesis, $k$ vertices are chosen at random and the edge weights between them are drawn from a distribution $Q$, while the remaining are sampled from $P$. The goal is to decide, upon observing the edge weights, which of the two hypotheses they were generated from. We investigate the problem under two different scenarios: (1) when $P$ and $Q$ are completely known, and (2) when there is only partial information of $P$ and $Q$. In the first scenario, we obtain statistical limits on $k$ when the two hypotheses are distinguishable, and when they are not. Additionally, in each of the scenarios, we provide bounds on the minimal risk of the hypothesis testing problem when $Q$ is not absolutely continuous with respect to $P$. We also provide computationally efficient spectral tests that can distinguish the two hypotheses as long as $k=\\Omega(\\sqrt{n})$ in both the scenarios.", "revisions": [ { "version": "v1", "updated": "2025-06-26T17:58:22.000Z" } ], "analyses": { "subjects": [ "62F03" ], "keywords": [ "detecting weighted hidden cliques", "hypothesis testing problem", "computationally efficient spectral tests", "classical hidden clique problem", "identically distributed edge weights" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }