Dear listers,
I have an 8-year panel of school district-level data. I need to calculate the mean of the year-to-year changes in enrollment-weighted spending. This is not as easy as it sounds, as the data are not weighted -- they're at the district level. I can't use the summ command to calculate a weighted average, because I need to calculate the mean of the weighted differences, not the weighted mean of the unweighted differences.
I can't figure out a way to "create" an enrollment-weighted spending variable. I tried to use the collapse command, but as you can see from the output below, something is wrong.
Any ideas? I'm frustrated by something so seemingly easy....
Thanks for your help,
Deb Garvey
. use "D:\school finance centralization\data\waoranal2"
. su instrpp [aw=adm] if year == 77 & statefip == 41
Variable | Obs Weight Mean Std. Dev. Min Max
-------------+-----------------------------------------------------------------
instrpp | 152 385645.500 948.8115 110.5098 610.7853 1802.382
. sort statefip sd_id year
. collapse instrpp [aw=adm], by(statefip sd_id year)
. su instrpp if statefip == 41 & year == 77
Variable | Obs Mean Std. Dev. Min Max
-------------+-----------------------------------------------------
instrpp | 152 976.8409 176.8611 610.7853 1802.382
******************************
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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