First Author:   Abdelkrim Araar CIRPEE aabd@ecn.ulaval.ca   2190, JA Desève, Laval University Sainte-Foy, G1K 7P4, Canada   1 418 656 7507(Phone) 1 418 656 7507(Fax) http://www.pep-net.org Second Author: Awoyemi Taiwo DEPARTMENT OF AGRICULTURAL ECONOMICS ttawoyemi@yahoo.com   , Nigeria       http://www.ui.edu.ng/deptofagriculturaleconomics.htm