  KKMC-hh is a hadronic event generator for Z boson production and decays,
which includes exponentiated multi-photon radiation and first-order electroweak
corrections. We have used KKMC-hh to investigate the role of initial sate
radiation (ISR) and initial-final interference (IFI) in precision electroweak
analyses at the LHC. We compare the effect of this radiation on angular
distributions and forward-backward asymmetry, which are particularly important
for the measurement of the weak mixing angle. We discuss the relation of the
ISR implementation in KKMC-hh to ISR from parton distribution functions with
QED corrections.
