🤖 AI Summary
This paper addresses the high bias and poor robustness of Bayesian posterior expectations and marginal likelihood (Bayesian evidence) estimation under high-dimensional, non-isotropic target distributions. To this end, we propose a target-aware Generalized Thermodynamic Integration (GTI) framework. Our core innovation is a learnable path parameterization that adaptively couples the integration path to the geometric structure of the target distribution, jointly optimizing the path via variational inference and refining sample efficiency through adaptive importance sampling. The GTI framework significantly reduces marginal likelihood estimation bias—achieving an average 38% reduction across multiple models—while improving posterior predictive consistency and computational stability. By explicitly encoding target-distribution geometry into the thermodynamic integration process, GTI establishes a more accurate and robust paradigm for high-dimensional Bayesian inference.