8f35ea1157a5d310VgnVCM100000c2b1d38dRCRDapproved/UMICH/stats/Home/People/Faculty/Faculty PublicationsRegularized estimation of large covariance matrices5f35ea1157a5d310VgnVCM100000c2b1d38d____Regularized estimation of large covariance matricesLevina, E.P. J. BickelelevinaAnnals of Statistics3612008199-227jjsantosjjsantos1363023572910