First Author:   Arcade Ndoricimpa Department of Economics, University of Dar Es Salaam, Tanzania arcade_ndoricimpa@yahoo.com   PO. BOX 35045 Dar es Salaam, TANZANIA       Second Author: Esther Leah Achandi Africa Rice Center, Dar Es Salaam, Tanzania leah_achandi@yahoo.com   PO BOX 33581 Dar es Salaam, TANZANIA