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...

During the early years of its existence, the National Bureau of Economic Research (NBER) assembled an extensive data set on all aspects of the pre-WWII macroeconomy. Until 1978, this data set existed only on the handwritten sheets to which the early NBER researchers copied the data from original...