st: Calculating predicted probabilities at a given value of one of the independent variables

[Maria Ana Vitorino <vitorino@wharton.upenn.edu>]

Dear Statalist users,

I would like to calculate some predicted probabilities after fitting a  
multinomial logit model (asclogit). But, the twist is that I would  
like to calculate these fitted values for a given level of one of the  
independent variables. Namely, I would like to set one of the Xs to  
zero when computing the predicted probability (but not in the  
estimation).
What would be the best way of going about this? Would it make sense to  
do it in 2 steps? In the first step use  "predict xb" and in the  
second step remove the component of xb that I'm not interested and  
calculate the probability using "gen" and the logit formula?
Or is there a better way?

Any thoughts are appreciated,
Ana
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