Nonparametric estimation of regression functions with both categorical and continuous data

In this paper we propose a method for nonparametric regression which admits continuous and categorical data in a natural manner using the method of kernels. A data-driven method of bandwidth selection is proposed, and we establish the asymptotic normality of the estimator. We also establish the rate of convergence of the cross-validated smoothing parameters to their benchmark optimal smoothing parameters. Simulations suggest that the new …