Benchmark Priors Revisited

Download or read book Benchmark Priors Revisited written by Stefan Zeugner and published by International Monetary Fund. This book was released on 2009-09-01 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Default prior choices fixing Zellner's g are predominant in the Bayesian Model Averaging literature, but tend to concentrate posterior mass on a tiny set of models. The paper demonstrates this supermodel effect and proposes to address it by a hyper-g prior, whose data-dependent shrinkage adapts posterior model distributions to data quality. Analytically, existing work on the hyper-g-prior is complemented by posterior expressions essential to fully Bayesian analysis and to sound numerical implementation. A simulation experiment illustrates the implications for posterior inference. Furthermore, an application to determinants of economic growth identifies several covariates whose robustness differs considerably from previous results.