Bose-Enhancement and Pauli-Blocking Effects in Transport Models
  The ability of semi-classical transport models to correctly simulate Pauli blocking and Bose enhancement is discussed. In the context of simple quantum mechanical systems, it is shown that using $(1 \pm f)$ enhancements is inadequate to describe systems far from equilibrium. The relaxation of $(1 + f)$ descriptions toward equilibrium is studied both in the context of simple models, including a hot pion gas confined to a box. We give simple estimates for the characteristic number of collisions for a system to relax toward equilibrium. 
Scott Pratt and Wolfgang Bauer