st: running regressions on only certain sections of the data

[Kit Baum <baum@bc.edu>]

Maarten said

I am assuming that you have a variable called section,
which contains the strings A, B, or C.
to do the regression you requested you would type:
reg y x if section == "A"
reg y x if section == "A" | section == "C"
reg y x if section == "A" | section == "B"

For more info see: - help if- and -help operator-



If you have many sections (but need no more than 10, categorized by a  
string variable) you could also do

reg y x if inlist(section,"A","C")
reg y x if inlist(section,"A","B")
...

help functions -> programming functions for details.  inrange() is  
also useful in some cases like this.

Kit Baum, Boston College Economics
http://ideas.repec.org/e/pba1.html
An Introduction to Modern Econometrics Using Stata:
http://www.stata-press.com/books/imeus.html


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