Affiliation: | 1Statistics Research Section, Australian National University G.P.O. Box 4, Canberra, A.C.T. 2601, Australia 2Department of Mathematics, Tulane University New Orleans, Louisiana 70118, U.S.A. 3Statistics Research Section, Australian National University G.P.O. Box 4, Canberra, A.C.T. 2601, Australia |