st: Obtaining Predicted Probabilities using gologit

[Lisa Powell <powelll@qed.econ.queensu.ca>]

HI,

I am running a gologit model and want to assess the magnitude of the 
association between one of my independent variables and my outcome 
variable using the predict option similar to a probit/logit model.  I 
specifically want to set my independent variable to a given value to test 
varying scenarios for this association.  Below is the syntax I used after 
my gologit model statement:


predict xb1, equation(mleq1) xb at [promo=1];
predict xb2, equation(mleq2) xb at [promo=1];
predict xb3, equation(mleq3) xb at [promo=1];
predict xb4, equation(mleq4) xb at [promo=1];
predict xb5, equation(mleq5) xb at [promo=1];


gen p1 = 1/(1+exp(-xb1));
gen p2 = 1/(1+exp(-xb2));
gen p3 = 1/(1+exp(-xb3));
gen p4 = 1/(1+exp(-xb4));
gen p5 = 1/(1+exp(-xb5));


gen prob1 = 1-p1;
gen prob2 = p1-p2;
gen prob3 = p2-p3;
gen prob4 = p3-p4;
gen prob5 = p4-p5;
gen prob6 = p5;


When I ran this I received the following error statement:


predict xb1, equation(mleq1) xb at [promo=1];
option at not allowed
r(198);



Does anyone know what the correct syntax is to set my independent variable 
to a specific value for the gologit predict option?


Thanks for your help,
Sandy Slater



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