A general or omnibus test of structure in social network data is proposed. The test exploits all of the information contained in the triad census. Analogous to the classical F-test for contrasts among means, the proposed test involves finding a weighting vector which maximizes a test statistic,...

The authors review the literature on the delivery of ambulatory care to the urban poor by isolating the crucial variables affecting the supply and demand for such services and organizing the literature around these concepts. The state of health of the poor, perception of health, and cost of care...

We introduce the concept of a triad census of a digraph arid show how it can be used to enumerate various types of subgraph configurations. We give the basic probabilities needed for computing means and variances for a triad census under the U-MAN distribution for digraphs. These concepts are...