This term adds one statistic to the model equal to the number of isolates in the network. For an undirected network, an isolate is defined to be any node with degree zero. For a directed network, an isolate is any node with both in-degree and out-degree equal to zero.
# binary: isolatesergmTerm for index of model terms currently visible to the package.
ergm:::.formatTermKeywords("ergmTerm", "isolates", "subsection")