Clustering with Non-adaptive Subset Queries

Neural Information Processing Systems 

Recovering the underlying clustering of a set U of n points by asking pair-wise same-cluster queries has garnered significant interest in the last decade. Given a query S U, |S| = 2, the oracle returns yes if the points are in the same cluster and no otherwise. We study a natural generalization of this problem to subset queries for |S| > 2, where the oracle returns the number of clusters intersecting S. Our aim is to determine the minimum number of queries needed for exactly recovering an arbitrary k-clustering. We focus on non-adaptive schemes, where all the queries are asked in one round, thus allowing for the querying process to be parallelized, which is a highly desirable property. For adaptive algorithms with pair-wise queries, the complexity is known to be Θ(nk), where k is the number of clusters.