Managing Editors Akira Yamazaki Meisei University Tokyo, JAPAN Shigeo Kusuoka University of Tokyo Tokyo, JAPAN Editors Robert Anderson University of California, Berkeley Berkeley, . Charles Castaing Universite Montpellier II Montpellier, FRANCE Frank H. Clarke Universite de Lyon I Villeurbanne, FRANCE Egbert Dierker University of Vienna Vienna, AUSTRIA Darrell Duffie Stanford University Stanford, . Lawrence C. Evans University of California, Berkeley Berkeley, . Takao Fujimoto Fukuoka University Fukuoka, JAPAN Jean-Michel Grandmont CREST-CNRS Malakoff, FRANCE Norimichi Hirano Yokohama National University Yokohama, JAPAN Leonid Hurwicz University of Minnesota MinneapoUs,