What is the problem when using the grqreg code?

[Kelsi Cheng]

hi, guys! I'm wondering a question that when I use grreq to plot the coefficient of quantile regression, strictly live up to the example it gives, but doesn't work.
The code in the example is：

. webuse auto, clear
. xi: qreg price mpg i.foreign*i.rep78 headroom
. grqreg, cons ci ols olsci

and the it hints:
o._IforXrep_1_2 invalid name

which means I can't add the dummy varibale in it, because when i delete the dummy, there is no problem, but once they are added, then it doesn't work

How can I solve this problem? I'm quite upset
Thanks soooo much!

[Kelsi Cheng]

anyone who caould help me,please~

[Wouter Wakker]

From Stata version 13 the use of factor variable notation was changed, making the xi prefix unnecessary. However, grqreg (from SSC, as you are asked to explain) was last updated in 2011, before Stata 13 came out. This works fine:

version 12
webuse auto, clear
xi: qreg price mpg i.foreign*i.rep78 headroom
grqreg, cons ci ols olsci

[Scott Merryman]

See: https://www.statalist.org/forums/for...88#post1431788

[Kelsi Cheng]

I SEE! Thanks so much!