W Boson Kinematic Analysis at the Tevatron: A comparison of ResBos   resummation and Pythia generator
  The kinematical features of the differential cross section distributions in inclusive W boson production at the Tevatron (ppbar -> W X -> e \u{psion}_e X) are presented using the resummation program ResBos, and the Monte Carlo event generator Pythia, and are found to be in marginal agreement with each other. While both programs reproduce the basic qualitative features of W boson, the distributions validate that Pythia can't be used as a reliable substitute for ResBos as far as the invariant mass of W boson and other electroweak precision measurements are concerned. 
Moh'd A. Hussein
hep-ph