quaids

[sakineh sojoodi]

Hi dear all
I want to estimate demand system for 13 goods using quaid command in stata 12. So I used the following command:
quaids w1-w13, anot(0) prices(p1-p13) expenditure(exp)
but i get following error:
number of price variables must equal number of equations (27 > )
what is problem? please advise me
Best regards

[Jorge Eduardo Perez Perez]

Are your variables ordered? To be able to use the w1-w13 syntax, variables must be in that order in the dataset.

order *, alphabetic
quaids w1-w13, anot(0) prices(p1-p13) expenditure(exp)