Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Compounding or mixture distributions provide a rich class of models for applications ranging from models of heterogeniety, measurement error, distribution of stock returns and income to models of unemployment duration. Some very general mixtures are considered which include many new mixture models and also provide a unified method of organizing and comparing previously considered models as well as a test of heterogeneity. These models are used to analyze CPS unemployment duration data. A heterogeniety interpretation of the mixture models explains the discrepancy between implications of search theory and patterns observed in aggregate unemployment data. Copyright 1987 by MIT Press.