Bootstrapping exchangeable random graphs*

Abstract

We introduce two new bootstraps for exchangeable random graphs. One, the “empirical graphon bootstrap”, is based purely on re-sampling, while the other, the “histogram bootstrap”, is a model-based “sieve” bootstrap. We show that both of them accurately approximate the sampling distributions of motif densities, i.e., of the normalized counts of the number of times fixed subgraphs appear in the network. These densities characterize the distribution of (infinite) exchangeable networks. Our bootstraps therefore give a valid quantification of uncertainty in inferences about fundamental network statistics, and so of parameters identifiable from them.