PAC Bayesian
PAC-Bayesian theory provides a frequentist framework for analyzing the generalization performance of machine learning models by incorporating prior knowledge, offering probabilistic generalization bounds. Current research focuses on extending PAC-Bayesian methods to high-dimensional settings, unbounded loss functions, and various model architectures including deep neural networks and generalized linear models, often employing techniques like importance weighting and regularized posteriors to improve bound tightness and practical applicability. These advancements yield tighter generalization guarantees and inform the design of more robust and efficient learning algorithms, impacting both theoretical understanding and practical applications across diverse machine learning domains.