Lee Sieswerda
>
> I was writing a reply to George Hoffman's question, when
> Vince Wiggins reply
> popped into my mail box. I have a question for Vince.
> First, here was what I
> was suggesting for George.
>
> bysort foreign: egen mean = mean(weight)
> bysort foreign: egen sd = sd(weight)
> bysort foreign: gen ub = mean +
> invttail(_N-1,.025)*(sqrt((sd^2)/_N))
> bysort foreign: gen lb = mean -
> invttail(_N-1,.025)*(sqrt((sd^2)/_N))
> twoway (rcap lb ub foreign) (scatter mean foreign)
>
> This gives the same results as -ci-. Specifically, it gives
> a 95% CI with
> the t critical value based on _N-1 observations within
> strata (of foreign in
> this case). It is -ci-'s results that I gather Nick Cox is
> using to produce
> his new -ciplot- (pardon me Nick, if I'm misrepresenting you).
Correct.
Nick
[email protected]
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