POISSON GRAVITY MODELS OF SPATIAL FLOWS*
整合了空间流模型的研究成果，基于泊松频率构建统一概率框架，发展出一类独立流过程，并推导出12种重力型流模型的层次分类及其行为公理刻画。
ABSTRACT The purpose of this paper is to bring together a number of results on spatial flow models, and to reformulate them within a unified probability framework based on Poisson frequencies. To do so, a class of discrete stochastic processes, designated as independent flow processes, is developed which not only yields a complete characterization of Poisson flow frequencies, but also allows a wide range of gravity‐type flow models to be formulated within this distributional framework. In particular, a hierarchical classification of 12 model types is developed, and each model type is shown to be characterizable directly in terms of behavioral axioms on independent flow processes.