author={Bala Rajaratnam and H{\'e}l{\`e}ne Massam and Carlos M. Carvalho},
  journal={Annals of Statistics},
In this paper, we propose a class of Bayes estimators for the covariance matrix of graphical Gaussian models Markov with respect to a decomposable graph G. Working with the W PG family defined by Letac and Massam [Ann. Statist. 35 (2007) 1278-1323] we derive closed-form expressions for Bayes estimators under the entropy and squared-error losses. The W PG family includes the classical inverse of the hyper inverse Wishart but has many more shape parameters, thus allowing for flexibility in… 

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