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Ranked masses in two-parameter Fleming-Viot diffusions

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 نشر من قبل Noah Forman
 تاريخ النشر 2021
  مجال البحث
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In previous work, we constructed Fleming--Viot-type measure-valued diffusions (and diffusions on a space of interval partitions of the unit interval $[0,1]$) that are stationary with the Poisson--Dirichlet laws with parameters $alphain(0,1)$ and $thetageq 0$. In this paper, we complete the proof that these processes resolve a conjecture by Feng and Sun (2010) by showing that the processes of ranked atom sizes (or of ranked interval lengths) of these diffusions are members of a two-parameter family of diffusions introduced by Petrov (2009), extending a model by Ethier and Kurtz (1981) in the case $alpha=0$. The latter diffusions are continuum limits of up-down Chinese restaurant processes.



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