User Guide

Chapter 13: Inferential Statistics and Distributions 235
2-SampFTest
2-SampÜTest (two-sample Ü-test; item E) computes an Ü-test to compare two normal population
standard deviations (s
1
and s
2
). The population means and standard deviations are all unknown.
2-SampÜTest, which uses the ratio of sample variances Sx1
2
/Sx2
2
, tests the null hypothesis
H
0
: s
1
=s
2
against one of the alternatives below.
•H
a
: s
1
ƒ
s
2
(s1:ƒs2)
•H
a
: s
1
<s
2
(s1:<s2)
•H
a
: s
1
>s
2
(s1:>s2)
In the example:
SAMP4={7,L4, 18, 17, L3, L5, 1, 10, 11, L2}
SAMP5={
L1, 12, L1, L3, 3, L5, 5, 2, L11, L1, L3}
Data Stats
Input:
Calculated
results:
Drawn results: