Let X, Y be continuous random variables with unknown distributions. The aim of this paper is to study the problem of estimating the probability \(\theta := {\mathbb {P}}(X<Y)\) based on independent random samples from the distributions of \(X'\) , \(Y'\) , \(\zeta \) and \(\eta \) , where \(X' = X + \zeta \) , \(Y' = Y + \eta \) and X, Y, \(\zeta \) , \(\eta \) are mutually independent random variables. In this context, \(\zeta \) , \(\eta \) are referred to as measurement errors. We apply the ridge-parameter regularization method to derive a nonparametric estimator for \(\theta \) depending on two parameters. Our estimator is shown to be consistent with respect to mean squared error if the characteristic functions of \(\zeta \) , \(\eta \) only vanish on Lebesgue measure zero sets. Under some further assumptions on the densities of X, Y, \(\zeta \) and \(\eta \) , we obtain some upper and lower bounds on the convergence rate of the estimator. A numerical example is also given to illustrate the efficiency of our method.