Introduction to Statistics (MAT/SST 115.03 2008S)
You can use R to compute the test statistic. Recall that this test statistic has the form
(x1bar - x2bar)/sqrt(s1*s1/n1 + s2*s2/n2)
You can fill in the values.
Okay, you need to compute
(xfbar-xfbar) +/- tkstar*sqrt(sf*sf/nf + sm*sm/nm)
I'll leave you to fill in the details.
As the book suggests, you can use the applet. You can also use
pt function to compute the
p-value. Since it's a two-sided test, we should
double the computed value.
t = (1.861-2.089)/sqrt(1.777*1.777/654 + 1.760*1.760/813) 2*pt(t, df=653)
Copyright (c) 2007-8 Samuel A. Rebelsky.
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