Before revision:  We then use an inductive "in-fill " and " out-expansion" algorithm to establish our main identification results. We also provide a formal analysis of normalization that is without loss of generality in a precise sense, and discuss its implications concerning the interpretation of the results and counterfactual analyses of the model .
After revision:  We then use an inductive "in-fill " and " out-expansion" algorithm to establish our main results, and consider extensions to more general settings that allow nonseparable dependence between homophily and degree heterogeneity .