st: re: excluding some cases for regression analysis

[Kit Baum <baum@bc.edu>]

Alice said

I have an unbalanced panel of more than 3000 firms. The firms have been
assigned id from 1 to 3256.
I was wonderting if i could exclude some firms (say id 45 to 560) when 
I run
any regression. How could I do so?

g want = ~ inrange(_n,45,560)
regress .... if want

Note that the ~ is NOT, so this is "I want those not in range 45, 560".
If you had more than one such range, define the dummies in terms of 
those you do NOT want, add up those dummies, and NOT the result.

g nowant1 = inrange(45,90)
g nowant2 = inrange(101,120)
g nowant3 = inrange(131,500)
g want = ~ (nowant1+nowant2+nowant3)

Kit Baum, Boston College Economics
http://ideas.repec.org/e/pba1.html

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