The interaction of size and density with graph-level indices

The size and density of graphs interact powerfully and subtly with other gr aph-level indices (GLIs), thereby complicating their interpretation. Here w e examine these interactions by plotting changes in the distributions of se veral popular graph measures across graphs of varying sizes and densities. We provide a generalized framework for hypothesis testing as a means of con trolling for size and density effects, and apply this method to several wel l-known sets of social network data; implications of our findings for metho dology and substantive theory are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.