  Very precise measurements of masses and cross sections, with errors of <1%,
are expected to be achievable with a future linear collider. Such an accuracy
gives sensitivity at the level of quantum corrections, which therefore must be
incorporated in order to make meaningful predictions for the underlying new
physics parameters. For the chargino-neutralino sector, this involves fitting
one-loop predictions to expected measurements of the cross sections and
forward-backward asymmetries and of the accessible chargino and neutralino
masses. Our analysis shows how an accurate determination of the desired
parameters is possible, providing in addition access to the mass of the lighter
stop.
