Local regression smoothers with set-valued outcome data

Abstract This paper proposes a method to conduct local linear regression smoothing in the presence of set-valued outcome data. The proposed estimator is shown to be consistent, and its mean squared error and asymptotic distribution are derived. A method to build error tubes around the estimator is provided, and a small Monte Carlo exercise is conducted to confirm the good finite sample properties of the estimator. The usefulness of the method is illustrated on a novel dataset from a clinical trial to assess the effect of certain genes' expressions on different lung cancer treatments outcomes.