Affiliation: | Department of Marketing, PHBA, University of Iowa, Iowa City, Iowa 52242.;To whom all correspondence should be addressed.;Decision Research, 1201 Oak St., Eugene, Oregon 97401.;Clark University, Center for Technology, Environment, and Development (CENTED), 950 Main Street, Worcester, Massachusetts 01610.;Brown University, Alan Shawn Feinstein World Hunger Program.;Center of Technology Assessment, Nobelstrasse 15, D-70, Stuttgart, Germany. |