BTW, anyone can tell me how Stata stores the value for "count"
command? Or referring me to some reference would be fine, thanks.
On 10/10/05, Sean <[email protected]> wrote:
> Many thanks Rafal; very helpful indeed. I'm in the process:)
>
> On 10/10/05, Rafal Raciborski <[email protected]> wrote:
> > Sean,
> >
> > Why not something like this?:
> >
> >
> > . use person, clear
> >
> > . list
> >
> > +--------------------------+
> > | personid bday bplace |
> > |--------------------------|
> > 1. | 1 1950 city1 |
> > 2. | 2 1951 city2 |
> > 3. | 3 1987 city2 |
> > 4. | 4 1950 city3 |
> > 5. | 5 1975 city1 |
> > +--------------------------+
> >
> > . use c1951, clear
> >
> > . list
> >
> > +-----------------------+
> > | city year pop |
> > |-----------------------|
> > 1. | city1 1951 10250 |
> > 2. | city2 1951 301872 |
> > 3. | city3 1951 65790 |
> > +-----------------------+
> >
> > . use c1950, clear
> >
> > . list
> >
> > +-----------------------+
> > | city year pop |
> > |-----------------------|
> > 1. | city1 1950 10000 |
> > 2. | city2 1950 300000 |
> > 3. | city3 1950 65000 |
> > +-----------------------+
> >
> > . append using c1951
> >
> > . sort city year
> >
> > . list
> >
> > +-----------------------+
> > | city year pop |
> > |-----------------------|
> > 1. | city1 1950 10000 |
> > 2. | city1 1951 10250 |
> > 3. | city2 1950 300000 |
> > 4. | city2 1951 301872 |
> > 5. | city3 1950 65000 |
> > |-----------------------|
> > 6. | city3 1951 65790 |
> > +-----------------------+
> >
> > . save city_big, replace
> > file city_big.dta saved
> >
> > .
> > . use person, clear
> >
> > . rename bday year
> >
> > . rename bplace city
> >
> > . sort city year
> >
> > . save person1, replace
> > file person1.dta saved
> >
> > .
> > . merge city year using city_big
> >
> > . drop if _merge==2
> > (3 observations deleted)
> >
> > . drop _merge
> >
> > . list
> >
> > +----------------------------------+
> > | personid year city pop |
> > |----------------------------------|
> > 1. | 1 1950 city1 10000 |
> > 2. | 5 1975 city1 . |
> > 3. | 2 1951 city2 301872 |
> > 4. | 3 1987 city2 . |
> > 5. | 4 1950 city3 65000 |
> > +----------------------------------+
> >
> > .
> > end of do-file
> >
> >
> > If your city datasets do not have a year variable in them, you can
> > easliy add it
> > using -forvalues-. Assuming your city datasets are named c1950, c1951, ... ,
> > c2000, you can use:
> >
> > forvalues i = 1950/2000 {
> > use c`i', clear
> > gen year = `i'
> > save, replace
> > }
> >
> > and then append and merge.
> >
> > Hope this helps.
> >
> > rafal
> >
> >
> > ================
> > Rafal Raciborski
> > Graduate student
> > Department of Political Science
> > Emory University
> > 301 Tarbutton Hall
> > 1555 Dickey Drive
> > Atlanta, GA 30322
> > 404-378-9826 (home)
> > [email protected]
> > http://www.roofoos.net/
> >
> >
> > *
> > * 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/
> >
>
>
> --
> Best Regards,
>
> Sean
>
--
Best Regards,
Sean
*
* 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/
