Neural Networks for Censored Expectile Regression Based on Data Augmentation
Wei Cao, Shanshan Wang
TL;DR
This work addresses censored data in expectile regression by introducing DAERNN, a data augmentation framework that imputes censored outcomes and iteratively updates ERNNs to estimate the $ au$-th conditional expectile $e_{ au}(Y|\boldsymbol{X})$ without requiring a parametric survival model. The method unifies right-, left-, and interval-censoring through a three-stage loop (data augmentation, model updating, prediction) and uses an MLP to model $m_{\tau}(\cdot)$ with MBGD optimization. Across simulations and two real datasets (WHAS and YVR), DAERNN consistently outperforms existing censored ERNNs (e.g., WERNN, DALinear) and achieves predictive performance close to full-data or oracle models, while maintaining reasonable computation time. This approach expands the applicability of censored ERNNs in risk, survival, and environmental contexts, though interpretability and high-dimensional scalability remain avenues for future work, including semiparametric hybrids and feature screening. The core ideas rely on seamlessly integrating data augmentation with neural expectile estimation to robustly handle censoring without explicit survival function specification, thereby delivering accurate, flexible modeling of heterogeneous distributions under censoring.
Abstract
Expectile regression neural networks (ERNNs) are powerful tools for capturing heterogeneity and complex nonlinear structures in data. However, most existing research has primarily focused on fully observed data, with limited attention paid to scenarios involving censored observations. In this paper, we propose a data augmentation based ERNNs algorithm, termed DAERNN, for modeling heterogeneous censored data. The proposed DAERNN is fully data driven, requires minimal assumptions, and offers substantial flexibility. Simulation studies and real data applications demonstrate that DAERNN outperforms existing censored ERNNs methods and achieves predictive performance comparable to models trained on fully observed data. Moreover, the algorithm provides a unified framework for handling various censoring mechanisms without requiring explicit parametric model specification, thereby enhancing its applicability to practical censored data analysis.
