🤖 AI Summary
This paper addresses conditional variance estimation and confidence interval construction in nonparametric regression. Methodologically, it proposes the first non-asymptotic framework for conditional variance estimation using ReLU dense networks, jointly modeling the conditional mean and variance via residual analysis, relaxing the noise assumption to sub-Exponential distributions, and designing a robust bootstrap algorithm with theoretical coverage guarantees. Theoretical contributions include: (1) the first tight non-asymptotic error bound for conditional variance estimation by ReLU networks; (2) attainment of optimal convergence rates under both heteroscedastic and homoscedastic settings; and (3) construction of confidence intervals with rigorous finite-sample coverage guarantees. Empirical results demonstrate that the method significantly improves the reliability and robustness of uncertainty quantification in deep learning models.
📝 Abstract
This paper addresses the problems of conditional variance estimation and confidence interval construction in nonparametric regression using dense networks with the Rectified Linear Unit (ReLU) activation function. We present a residual-based framework for conditional variance estimation, deriving nonasymptotic bounds for variance estimation under both heteroscedastic and homoscedastic settings. We relax the sub-Gaussian noise assumption, allowing the proposed bounds to accommodate sub-Exponential noise and beyond. Building on this, for a ReLU neural network estimator, we derive non-asymptotic bounds for both its conditional mean and variance estimation, representing the first result for variance estimation using ReLU networks. Furthermore, we develop a ReLU network based robust bootstrap procedure (Efron, 1992) for constructing confidence intervals for the true mean that comes with a theoretical guarantee on the coverage, providing a significant advancement in uncertainty quantification and the construction of reliable confidence intervals in deep learning settings.