[1] Univ Antioquia, Dept Econ, Fac Ciencias Econ, Dept Estadist & Matemat, Medellin, Colombia
[2] Univ Nacl Colombia, Fac Ciencias Humanas & Econ, Dept Econ, Medellin, Colombia
[3] Univ Antioquia, Grp Econometria Aplicada, Fac Ciencias Econ, Medellin, Colombia