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.