Thanks to Thomas Steichen for his suggestion (below). Oddly enough, Stata doesn't appear to care whether a delimiter is present after the -forval- command or after the command initially following -forval-.
My error was in the use of the -gen- statement. I needed to initialize the variables to 0 for all observations and then replace with time trend values for the appropriate group/year combination. My old code (naturally) set the time trend variables to missing except for the particular group/year combination to which the -gen- condition applied.
The correct -forval- loop is below.
Best,
Deb Garvey
forval i = 1/52 {
gen time`i' = 0;
gen timep`i' = 0;
replace time`i' = year - 74 if group == `i';
replace timep`i' = (year - 79)*(year >=80) if group == `i';
};
"Steichen, Thomas" <[email protected]> wrote:
It looks like there is a missing ; after line
. forval i = 1/`r(max)' {
> -----Original Message-----
> From: Deborah Garvey [mailto:[email protected]]
> Sent: Friday, August 15, 2003 2:49 PM
> To: [email protected]
> Subject: st: Trouble with -forval- and -gen- new variables
>
>
> Hi, all.
>
> I hate to trouble the list with such a simple problem, but I
> can't figure out what is wrong with my code. I am attempting
> to generate a series of state-specific and national time
> trends for a 12-year panel of data using -forval- like an
> obedient Stata user instead of the now-defunct -for- command.
>
> I am running Intercooled Stata 7.0 for Win98/95/NT (Born: 11
> June 2002). Annotated log file follows:
>
> use "D:\school finance centralization\data\StatAbstract
> data\stateexpY7586";
>
> . keep fipsst pubst state tsrgex* rexcap* rgexed* rgexpw*
> rcapy* rpery*
> > rexk12* k12pct* rppe*;
>
> . unab vars: *79;
>
> . local stubs: subinstr local vars "79" "", all;
>
> . reshape long `stubs', i(fipsst) j(year);
> (note: j = 75 76 77 78 79 80 81 82 83 84 85 86)
> (note: k12pct75 not found)
> (note: rexk1275 not found) --> OK. Missing exp data in 1975
> (note: rppe75 not found)
>
> Data wide -> long
> --------------------------------------------------------------
> ---------------
> Number of obs. 52 -> 624
> Number of variables 108 -> 13
> j variable (12 values) -> year
> xij variables:
> k12pct75 k12pct76 ... k12pct86 -> k12pct
> tsrgex75 tsrgex76 ... tsrgex86 -> tsrgex
> rexcap75 rexcap76 ... rexcap86 -> rexcap
> rgexed75 rgexed76 ... rgexed86 -> rgexed
> rgexpw75 rgexpw76 ... rgexpw86 -> rgexpw
> rcapy75 rcapy76 ... rcapy86 -> rcapy
> rpery75 rpery76 ... rpery86 -> rpery
> rexk1275 rexk1276 ... rexk1286 -> rexk12
> rppe75 rppe76 ... rppe86 -> rppe
> --------------------------------------------------------------
> ---------------
>
> . gen lrppe = ln(rppe);
> (52 missing values generated)
>
> . egen group = group(fipsst), missing;
>
> . su group, meanonly;
>
> . di `r(max)';
> 52
>
> . forval i = 1/`r(max)' {
> > gen time`i'= year - 74 if group == `i';
> 2. gen timep`i' = (year - 79)*(year >=80) if group == `i';
> 3. };
> (612 missing values generated)
> [<<snip>> Repeated 104 times (=52 groups *2 vars)]
>
> Summing by group & year shows that time* and timep* are
> non-missing, valid only for group 1. For all other
> groups/year combinations, both variables are missing (=51*12 = 612).
>
> . by group year: su time1 timep1 year fipsst;
>
> ____________________________________________________________
> -> group = 1, year = 75
>
> Variable | Obs Mean Std. Dev. Min Max
> -------------+-----------------------------------------------------
> time1 | 1 1 . 1 1
> timep1 | 1 0 . 0 0
> year | 1 75 . 75 75
> fipsst | 1 1 . 1 1
>
> <<snip>>
>
> What am I doing wrong? It doesn't matter if I substitute the
> number of groups (52) for the `rmax' saved result in the
> -forval- command.
>
> The program runs perfectly if I substitute -for- commands for
> the -forval- loop: for num 1/`r(max)': gen timeX = (year -
> 74)*(group == X); for num 1/52: gen timepX = (year -
> 79)*(group == X)*(year >=80);
>
> Thanks for any assistance you care to offer.
>
> Deb Garvey
>
>
******************************
Deborah Garvey, Ph.D.
Department of Economics
Kenna Hall
Santa Clara University
Santa Clara, CA 95053
408/554-5580
408/554-2331 (FAX)
[email protected]
http://lsb.scu.edu/~dgarvey
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