Random Discrete Distributions Invariant Under Size - biased Permutation
نویسنده
چکیده
Invariance of a random discrete distribution under size-biased permutation is equivalent to a conjunction of symmetry conditions on its nite-dimensional distributions. This is applied to characterize residual allocation models with independent factors that are invariant under size-biased permutation. Apart from some exceptional cases and minor modiications, such models form a two-parameter family of generalized Dirichlet distributions.
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