Bayesian Nested Group Lasso
摘要
We introduce the Bayesian Nested Group Lasso, a hierarchical model extending the Group Lasso to nested structures. By formulating the penalty as a scale mixture of Gaussians, we derive an efficient MCMC sampling scheme. A simulation study shows that our method reduces posterior variability for irrelevant variables, outperforming the Bayesian Lasso in structured sparsity settings. We discuss potential extensions, including spike-and-slab priors, for exact variable selection.