<~> IEEE SYSTEMS SCIENCE AND CYBERNETICS GROUP

The Systems Science and Cybernetics Group is an organization, within the framework of the IEEE, with professional interest in the closely interrelatedfields of systems science, systems engineering, and cybernetics. All members of the IEEE are eligible for membership and will receive this TRANSACTIONSupon payment of the annual Group membership fee of $4.00. Members of certain other professional societies are eligible to become Affiliates of the Group.For information on joining, write to the IEEE at the address below.

ADMINISTRATIVE COMMIITEE

ChairmanR. W. HOUSE

SecretaryH. S. KIRSCHBAUM

Term Ending 1968

M. L. BABCOCKH. CHESTNUTR. W. HOUSEM. KATZW. D. RowE

TreasurerA. D. HALL

First Vice ChairmanR. R. DOUGAN

Term Ending 1969

J. G. BRAINERDG. L. HOLLANDERH. L. OESTREICHERJ. REITMAN

Second Vice ChairmanD. B. BRICK

Term Ending 1970

A. D. HALLR. A. HOWARDR. E. MACHOLJ. MILSUMW. H. VON ALVEN

IEEE TRANSACTIONS® ON SYSTEMS SCIENCE AND CYBERNETICS

Editor

JOHN N. WARFIELDBattelle Memorial InstituteColumbus, Ohio 43201

W. R. ASHBYUniversity of IllinoisUrbana, Ill.

D. B. BRICKInformation Research Assoc.Lexington, Mass.

R. A. BROWNUniversity of AlabamaHuntsville, Ala.

Associate Editors

L. FEIN431 Ferne AvenuePalo Alto, Calif.

T. J. HIGGINSUniversity of WisconsinMadison, Wis.

A. LAVICarnegie-Mellon UniversityPittsburgh, Pa.

M. G. REKOFFBell Telephone Labs., Inc.Whippany, N. J.

L. STARKUniversity of IllinoisChicago, Ill.

T. M. STOUTProfimatics, Inc.Canoga Park, Calif.

PUBLISHED BY THE INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, INC.345 East 47 Street, New York, N. Y. 10017

OfficersS. W. HERWALD, PresidentL. C. HOLMES, Vice PresidentJ. H. MULLIGAN, JR., Vice President, Technical Activities

F. K. WILLENBROCK, Vice President, Publication ActivitiesW. G. SHEPHERD, SecretaryHAROLD CHESTNuT, Treasurer

Headquarters StaffDONALD G. FINK, General Manager

JOHN L. CALLAHAN, Staff Consultant JOHN M. KINN, Director, Educational ServicesRICHARD M. EMBERSON, Director, Technical Services LEON PODOLSKY, Staff ConsultantRALPH H. FLYNN, Director, Publishing Services BETTY J. STILLMAN, Administrative Assistant to the General ManagerELWOOD K. GANNETT, Director, Editorial Services HOWARD E. TOMPKINS, Director, Information ServicesWILLIAM J. KEYES, Director, Administrative Services

Editorial Department

HELENE FRISCHAUER, Administrative EditorAssistant Editors: HELEN GOLDMAN, BONNIE SILVERSTEIN, INGEBORG M. STOCHMAL

Senior Editorial Assistants: JoY COLVIN, GAIL S. FERENC, SANDRA GREER, SYLVIA R. JACOBS, JOAN W. STERN

Responsibility for the contents rests upon the authors and not upon the IEEE, the Group, or its members. Individual copies may be purchased at thefollowing prices: IEEE members (one copy) $2.50; public libraries and colleges $3.75 in U.S.A. and Canada, $4.25 elsewhere. Others $5.00 in U.S.A. andCanada, $5.50 elsewhere. Annual subscription price: IEEE members, dues plus Group fee. Price for nonmembers available on request. Abstracting ispermitted with mention of source. All rights, including translation, are reserved by the IEEE. Requests for republication permission should be addressedto the IEEE Editorial Department, 345 East 47 Street, New York, N.Y. 10017. Copyright © 1968 by The Institute of Electrical and Electronics Engineers,Inc. Printed in U.S.A.