Greetings,
In some survey data, I have three variables that measure whether a given
school improvement strategy is used with each of three types of schools,
A, B, and C. (Variables d1a, d1b, d1c -- d1a codes as a 0/1 whether or
not strategy one is used with school type A; d1b records the same thing
for school type b, and so on).
I'm interested in testing whether a strategy is used differentially for
different types of schools. If there were two school types, this would
be easy -- simply -ttest- that the two variables are equal:
. ttest d1a = d1b
But with three, it gets more complex.
One approach, since this is survey data, is to first use -svymean- to
get the means of all three, then test jointly that a=b and a=c:
. svymean d1a d1b d1c, complete
. svytest d1a=d1b, notest
. svytest d1a=d1c, accum
Another approach would be to set it up as a repeated measures ANOVA --
reshaping to long format, and treating the three types as a repeated
measure. But with thousands of cases, this seems cumbersome at best.
Thoughts?
Thanks,
Nick Winter
-----------------------------------------------------------
Nicholas Winter, Ph.D. P 202.939.5343
Policy Studies Associates F 202.939.5732
1718 Connecticut Avenue, NW [email protected]
Washington, DC 20009-1148 www.policystudies.com
-----------------------------------------------------------
<<winmail.dat>>