Patterns of Non-exponential Growth of Macroeconomic Models: Two-Parameter Poisson-Dirichlet Models

This paper discusses non-exponential growth patterns of macroeconomic models. More specifically, the paper discusses asymptotic growth patterns of the numbers of clusters and of components of partition vectors, that is, the number of clusters of specific sizes, of one- and two-parameter Poisson- Dirichlet models as the model sizes grow towards infinity. As the model sizes become large, the coefficients of variaation of the cluster sizes and components of the partition vector tend to zero in one-parameter Poisson-Dirichlet model, but they remain positive in the two-parameter version. Furthermore, the two-parameter version of the model exhibits power-law behavior, while the oneparameter version does not. The growth behavior of the two-parameter models is shown to be expressed in terms of generalized Mittag-Leffler distributions. The paper ends with preliminary discussion of the effects of demand pattern management policies on growth patterns of models that endogenize the parameters of the two-parameter Poisson-Dirichlet model.