Displaying 1 result from an estimated 1 matches for "s_pooled".
2007 Nov 07
1
Homework help: t test hypothesis testing with summarized data?
Is this how a t hypothesis test is done when I don't have the actual
data, but just the summarized statistics:
> #Homework 9.2.6 [1]
> n<-31
> xbar<-3.10
> s_x<-1.469
> m<-57
> ybar<-2.43
> s_y<-1.35
> s_pooled<- (((n-1)*s_x^2) + ((m-1)*s_y^2)) / (n + m - 2)
> s_pooled
[1] 1.939521
> t_obs <- (xbar - ybar) / (s_pooled * (sqrt(1/n + 1/m)))
> t_obs
[1] 1.547951
> qt(c(.025, .975), n+m-2)
[1] -1.987934 1.987934
> # Therefore, fail to reject H0 at the 0.05 level of significance
>
Or...