The two-parameter Ewens distribution: a finitary approach
Tóm tắt
The well-known Ewens Sampling Formula has been generalized by Pitman recently. We derive some essential feature of the model without introducing notions like frequency spectrum, structure distribution or size-biased permutation invariance, that are difficult to apply to concrete finite populations. A finite model of economic interacting agents whose equilibrium aggregation state is described by the two-parameter Ewens distribution is presented. The exact marginal description of a site is derived, wherefrom birth, life and death of clusters is easy to extract; and a code for computer simulations of the life of clusters is enclosed.
Tài liệu tham khảo
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