[Gretl-users] Probit marginal effects

Dear Gretl Community, I'm trying to replicate the slope calculations that Gretl exhibits on Probit estimation. In most of the time I can replicate exactly the same numbers, but there are some cases that I can not (i.e. the values are different). Please take a look at the following Hansl code: <hansl> set messages off set echo off ############ Ok! ############# open transport.gdt probit auto autotime bustime list lista = $xlist loop foreach i lista --quiet series med_$i = mean($i) endloop list med_lista = med_* matrix med_me_matrix = dnorm(lincomb(med_lista, $coeff))*$coeff' matrix me = med_me_matrix[1,] printf "\nMarginal effects:\n %12.6f \n", me ############ Not ok! ############# open greene19_1 probit GRADE GPA PSI list lista = $xlist loop foreach i lista --quiet series med_$i = mean($i) endloop list med_lista = med_* matrix med_me_matrix = dnorm(lincomb(med_lista, $coeff))*$coeff' matrix me = med_me_matrix[1,] printf "\nThe marginal effects: %12.8f \n", me </hansl> Thanks in advance, Henrique Andrade