This article is the first working paper of the Researching Center for Agricultural Sciences and Applied Economic. It is a contribution for the INTA Nicaragua.

This paper don�t was submitted on the conference, however the author participated on the event. He member of the European Association of Agricultual Ecnomist (EAAE)

Selected Paper prepared for presentation at the International Association of Agricultural Economists (IAAE) Triennial Conference, Foz do Iguaçu, Brazil, 18-24 August, 2012