How best to do this is controversial, but I think many statistical
people would expect you to recast your problem as one for -anova- or
-oneway- followed by whatever tests you think best. I don't think lots
of pairwise t-tests win widespread approval.
However, only you can say whether and in what sense the years are
independent. Perhaps this should be a repeated measures ANOVA.
Nick
[email protected]
Lloyd Dumont
I am using -ttest- in combination with -bys- to do group mean comparison
tests by the variable YEAR. Specifically, the command is...
bys YEAR: ttest REV if inlist(TYPE,1,3), by(TYPE)
My issue is this:
It does the test three separate times, i.e., for each value of YEAR.
That is perfect. But, aside from generating three separate t-tests for
the difference-in-means, is there a way for me to evaluate the three
tests jointly, with a single test statistic? In other words, let's say
that for 2 of the 3 years, I can reject the null. But, I cannot reject
the null for the 3rd year. Can I test the joint hypothesis that I can
reject the null across the 3 years?
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