Re: st: question about egen

[Shige Song <sgsong@ucla.edu>]

Sarah,

I am trying to construct that variables in the way that can be easily 
collapsed into the format that each city has one record, so it reads:

city    np      nw      nm      ...
a       1000    580     420
b       1200    620     380
c       3000    500     500
...

The way you proposed does not seem to make this easy. But thank you very 
much for the reply!

Best,
Shige

At 10:03 PM 4/17/2003 -0400, you wrote:

> Shige -
>
> If you just tabulate CITY, doesn't that tell you the total number of 
> people living in each city (unless your dataset has multiple obs per 
> person or something like that)?
>
> I may not understand what you are trying to do, but based on what you said 
> about wanting to create variables that show 1) number of men in each city, 
> 2) number of women in each city, and 3) total number of people in each 
> city, can't you:
>
> gen nm=city if gender==1
> gen nw=city if gender==2
> gen np=city
>
> ?
>
> Sarah
>
> --On Thursday, April 17, 2003 6:33 PM -0700 Shige Song <sgsong@ucla.edu> 
> wrote:
>
>
> > Dear All,
> >
> > I am trying to use "egen newvar = count()" to generate a set of variables
> > indicating frequency of old variables. The syntax is (as stated in the
> > Reference manual):
> >
> >         egen nwear = count(exp)
> >
> > I was wondering what this "(exp)" means (there is no example for this
> > particular type of egen).
> >
> > For example, I have variable GENDER (1: men, 2: women), CITY(a, b,
> > c,d,e,f). I want to generate variables that show 1) number of men in each
> > city, 2) number of women in each city, and 3) total number of people in
> > each city. So I type:
> >
> >         sort CITY
> >         by CITY: egen nm=count(GENDER==1)
> >         by CITY: egen nw=count(GENDER==2)
> >         by CITY: egen np=count(GENDER)
> >
> > Stata generates all three variables with complains, but surprisingly, all
> > three new generated variables are exactly identical (all equal the total
> > number of people)! Can anyone please give me a hand? Thank you very much!
> >
> > Best,
> > Shige Song
> > Department of Sociology, UCLA
> >
> > *
> > *   For searches and help try:
> > *   http://www.stata.com/support/faqs/res/findit.html
> > *   http://www.stata.com/support/statalist/faq
> > *   http://www.ats.ucla.edu/stat/stata/
>
>
> Sarah A. Mustillo, Ph.D
> Center for Developmental Epidemiology
> Department of Psychiatry and Behavioral Sciences
> Duke University School of Medicine
> Box 3454
> Durham NC 27710
>
> 919 687-4686 x234
> *
> *   For searches and help try:
> *   http://www.stata.com/support/faqs/res/findit.html
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/
*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/