How to find Gini coefficient per group?

[Ana Maiorova]

Hey there, inexperienced Stata user here. I have read FAQ but did not find the answer to my question..So I would love to find the Gini coefficient for each prvince. I have tried to run ineqdeco percy , by(prov), but received r(2000) error and the message "no observations".

[Ana Maiorova]

Update: For the experiment I tried to run ineqdeco percy, by(region). Region is a numeric value, and it worked. I guess the problem is that "prov" is a non-numeric value?

[Nick Cox]

ineqdeco is from SSC. The rule is explained in the help:

groupvar must take non-negative integer values only. To create such a variable from an existing variable, use the egen function group.

In fact, you may be using an out-of-date version of ineqdeco. The error message I got was more informative:

string variables not allowed in option bygroup();