prediction accuracy mlogit

I am trying to perform a multilogistic model using stata.
I used the command :
mlogit TargetGroup  PA_Score cigarweek cigwee age3 qw2
In standard logistic regression the solution would be the command
class estat

I have found this script online :
// mlogit
webuse sysdsn1, clear
mlogit insure age male nonwhite
predict prob*
egen pred_max = rowmax(prob*)

g pred_choice = .
forv i=1/3 {
 replace pred_choice = `i' if (pred_max == prob`i')
local insure_lab: value label insure
label values pred_choice `insure_lab'
tab pred_choice insure
But I am not able to reproduce it.

Can someone explain me how to get the accuracy of my model?
The percentage of correct estimation?