[1] Univ Calif Davis, Dept Agr & Resource Econ, Giannini Fdn Agr Econ, 3108 Social Sci & Humanities, Davis, CA 95616 USA
[2] Univ Laval, Fac Sci Adm, Dept Finance Insurance & Real Estate, Pavillon Palasis Prince,2325 Rue Terrasse, Quebec City, PQ G1V 0A6, Canada