Power of test
Ethan Johnsons wrote:
What would be the R formulae for a two-sided test?
I have a formula for a one-sided test:
powertest <- function(a,m0,m1,n,s){
t1 = -qnorm(1-a)
num = abs(m0-m1) * sqrt(n)
t2 = num/s
pow = pnorm(t1 + t2)
}
Would you pls let me know if you know of?
RSiteSearch("power", restrict="functions") is helpful. For a comparison
of two means, the most relevant hit is probably:
http://finzi.psych.upenn.edu/R/library/stats/html/power.t.test.html
Thank you, ej
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