Chapter 13: Inferential Statistics and Distributions
228
2-PropZTest
2-PropZTest
(two-proportion
z
test; item
6
) computes a test to compare the proportion of successes
(p
1
and p
2
) from two populations. It takes as input the count of successes in each sample (
x
1
and
x
2
) and the count of observations in each sample (
n
1
and
n
2
).
2-PropZTest
tests the null hypothesis
H
0
: p
1
=p
2
(using the pooled sample proportion
Ç
) against one of the alternatives below.
•
H
a
: p
1
ƒ
p
2
(
p1:
ƒ
p2
)
•
H
a
: p
1
<p
2
(
p1:<p2
)
•
H
a
: p
1
>p
2
(
p1:>p2
)
Input:
Calculated
results:
Drawn
results:
