Principal Editors M.J. Goovaerts

J. Wimp

L. Wuytack

lnstituut voor Aktuariele Wetenschappen, Katholieke Universiteit Leuven, Dekenstraat 2, B-3000 Leuven, Belgium Department of Mathematics and Computer Science, Drexel University, Philadelphia, PA 19104, United States Departement Wiskunde en Informatica, Universitaire Instelling Antwerpen, Uni- versiteitsplein 1, B-261 0 Antwerpen (Wilrijk), Belgium

Algorithms Editor R. Piessens Departement Computerwetenschappen, Katholieke Universiteit Leuven, Celestijnen-

laan 200 A, B-3001 Heverlee, Belgium

‘Letter Section’ Editors T.J. Oden

P.J. van der Houwen

Department of Aerospace Engineering and Engineering Mechanics, University of Texas, Austin, TX 78712, United States Afdeling Numerieke Wiskunde, Centrum voor Wiskunde en Informatica, Postbus 4079, 1009 AB Amsterdam, Netherlands

Associate Editors 0. Axelsson

C.T.H. Baker

C. Brezinski

F. Broeckx

H. Brunner

H. Buhlmann L. Collatz

B. Davies

C.W. Gear W. Gochet

W.B. Gragg

C.C. Grosjean

M.H. Gutknecht A. Hadjidimos

R. Jeltsch D.K. Kahaner

D.P. Laurie

J. Lehn

F.G. Lether T.-T. Li T. Lyche

Mathematisch Instituut, Faculteit der Wiskunde en Natuurwetenschappen, Katholieke Universiteit Nijmegen, Toernooiveld, 6525 ED Nijmegen, Netherlands Department of Mathematics, University of Manchester, Oxford Road, Manchester, United Kingdom Ml3 9PL Universite des Sciences et Techniques de Lille, 59655 Villeneuve d’Ascq Cedex, France Departement Toegepaste Economic, Rijksuniversitair Centrum Antwerpen, Middel- heimlaan 1, B-2020 Antwerpen, Belgium Department of Mathematics and Statistics, Memorial University of Newfoundland, St. John’s, Newfoundland, Canada Al C 5S7 Eidgenossische Technische Hochschule, CH-8092 Zurich, Switzerland lnstitut fur Angewandte Mathematik, Universitat Hamburg, Edmund-Siemens-Allee 1, W-2000 Hamburg, Germany Department of Mathematics, Australian National University, G.P.O. 4, Canberra, ACT 2601, Australia NEC Research Institute, 4 Independence Way, Princeton, NJ 08540, United States Departement Toegepaste Economische Wetenschappen, Katholieke Universiteit Leuven, Dekenstraat 2, B-3000 Leuven, Belgium Department of Mathematics, University of South Florida, Tampa, FL 33620, United States Laboratorium voor Numerieke Wiskunde en Informatica, Rijksuniversiteit te Gent, Krijgslaan 281, gebouw S9, B-9000 Gent, Belgium ETH-Zentrum, CH-8092 Zurich, Switzerland Department of Computer Sciences, Purdue University, West Lafayette, IN 47907, United States Seminar fur Angewandte Mathematik, ETH-Zentrum, CH-8092 Zurich, Switzerland Center for Computational and Applied Mathematics, NIST, Gaithersburg, MD 20899, United States Department of Mathematics and Applied Mathematics, Potchefstroom University for Christian Higher Education, Vaal Triangle Campus, Vanderbijlpark 1900, South Africa Arbeitsgruppe Stochastik und Operations Research, Technische Hochschule Darm- stadt, SchloOgartenstraOe 7, W-61 00 Darmstadt, Germany Department of Mathematics, University of Georgia, Athens, GA 30602, United States Department of Mathematics, Fudan University, Shanghai, China Institute of Informatics, University of Oslo, P.O. Box 1080, Blindern, 0316 Oslo 3, Norway

J. Meinguet

M. Mori

J. Oliger

N. Papamichael

L. Reichel

O.G. Ruehr

I.H. Sloan

M.N. Spijker

F. Stummel

K. Tanabe

L.N. Trefethen

H. van der Vorst

P. van Dooren

R.-H. Wang T. Yamamoto

Departement de Mathematiques Appliquees, Universite Catholique de Louvain, Place de I’Universite 1, B-1348 Louvain-la-Neuve, Belgium Department of Applied Physics, Faculty of Engineering, University of Tokyo, 7-l-l Hongo, Bunkyo-ku, Tokyo 113, Japan Department of Computer Science, Stanford University, Stanford, CA 94305, United States Department of Mathematics & Statistics, Brunel University, Uxbridge, Middlesex, United Kingdom UB8 3PH Department of Mathematics, University of Kentucky, Lexington, KY 40506-0027, United States Department of Mathematical and Computer Sciences, Michigan Technological Univer- sity, Houghton, Ml 49931, United States School of Mathematics, University of New South Wales, Kensington, NSW 2033, Australia Subfaculteit der Wiskunde, Rijksuniversiteit Leiden, Stationsweg 46, 2313 AV Leiden, Netherlands Fachbereich Mathematik, Johann Wolfgang Goethe-Universitat, Robert-Mayer-Stral3e 6-10, W-6000 Frankfurt am Main, Germany The Institute of Statistical Mathematics, 4-6-7 Minami-Azabu, Minato-Ku, Tokyo 106, Japan Department of Mathematics, Massachusetts Institute of Technology, Room 2-236, 77 Massachusetts Avenue, Cambridge, MA 02139, United States Mathematisch Instituut, Universiteit Utrecht, P.O. Box 80010, 3508 TA Utrecht, Nether- lands Research Laboratory Brussels, Philips & MBLE Associated S.A., Avenue Van Betel - aere 2, Box 8, B-l 170 Brussels, Belgium Institute of Applied Mathematics, Dalian University of Technology, Dalian, China Department of Mathematics, Faculty of Science, Ehime University, Matsuyama 790, Japan