Title: The two-parameter generalization of Ewens' random partition structure
Author: Jim Pitman
Date: March 1992; reprinted with an appendix and updated references July 2003
pub: PDF
Url: http://www.stat.berkeley.edu/~pitman/345.pdf
Abstract: A two-parameter generalization of Ewens' random partition structure is obtained
by sampling from a random discrete distribution derived by Perman, Pitman and Yor from the 
lengths of excursions of a recurrent Bessel process.