Hurwicz has received six honorary doctorates ( PhD ) , from Northwestern University ( 1980 ) , the University of Chicago ( 1993 ) , Universitat AutÃ noma de Barcelona ( 1989 ) , Keio University ( 1993 ) , Warsaw School of Economics ( 1994 ) and UniversitÃ t Bielefeld ( 2004 ) . Hurwicz received six honorary doctorates , from Northwestern University ( 1980 ) , the University of Chicago ( 1993 ) , Universitat AutÃ noma de Barcelona ( 1989 ) , Keio University ( 1993 ) , Warsaw School of Economics ( 1994 ) and UniversitÃ t Bielefeld ( 2004 ) .