PRECISE CALCULATION OF M(W), SIN(2)(THETA)OVER-CAP(W)(M(Z)), AND SIN(2)THETA(EFF)(LEPT)

The two-loop O(g(4)M(t)(2)/M(w)(2)) corrections are incorporated in th e theoretical calculation of M(w), sin(2)<(theta)over cap>(w)(M(z)), a nd sin(2) theta(eff)(lept), as functions of Mr. The analysis is carrie d out in a previously proposed MS formulation and two novel on-shell r esummation schemes. It is found that the inclusion of the new effects sharply decreases the scheme and residual scale dependence of the calc ulations. QCD corrections are incorporated in two different approaches , Comparison with the world average of sin(2) theta(eff)(lept) leads t o M(H) = 127(-71)(+143) GeV and M(w) = 80.367 +/- 0.048 GeV, with smal l variations among the six calculations.