On WAIC for Dependent Data: A Covariance-Corrected Framework with Linear-Time Complexity
依赖数据下的 WAIC:线性时间复杂度的协方差修正框架
The Widely Applicable Information Criterion (WAIC) is a cornerstone of Bayesian model selection, but its conditional independence assumption renders it inappropriate for sequential and spatially correlated data - a limitation that leads to systematically underestimated model complexity and over-optimistic predictive assessments. We introduce CC-WAIC, a principled generalization of WAIC that explicitly incorporates the full posterior covariance structure of log-likelihood…