The following MINITAB output display presents the results of a hypothesis test on the difference between two proportions. Test and CI for Two Proportions: P1, P2
$\begin{array}{lccc}
\text { Variable } & \mathrm{X} & \mathrm{N} & \text { Sample P } \
\text { P1 } & 56 & 94 & 0.595745 \
\mathrm{P} 2 & 34 & 72 & 0.472222
\end{array}$

Difference $= p ( \mathrm { P } 1 ) = p ( \mathrm { P } 2 )$
Estimate for differenc 0.123523
$95 \%$ CI for difference: $( - 0.02941,0.276456 )$
T-Test of difference $= 0 ($ vs not $= \mathbb { 0 } ):Z = 1.583084 \mathrm { P }$-Value $= 0.113402$ Is this a left-tailed test, a right-tailed test, or a two tailed test?
A) Left-tailed test
B) Two-tailed test
C) Right-tailed test

Question

The following MINITAB output display presents the results of a hypothesis test on the difference between two proportions. Test and CI for Two Proportions: P1, P2
$\begin{array}{lccc}
\text { Variable } & \mathrm{X} & \mathrm{N} & \text { Sample P } \
\text { P1 } & 56 & 94 & 0.595745 \
\mathrm{P} 2 & 34 & 72 & 0.472222
\end{array}$

Difference $= p ( \mathrm { P } 1 ) = p ( \mathrm { P } 2 )$
Estimate for differenc 0.123523
$95 \%$ CI for difference: $( - 0.02941,0.276456 )$
T-Test of difference $= 0 ($ vs not $= \mathbb { 0 } ):Z = 1.583084 \mathrm { P }$-Value $= 0.113402$ Is this a left-tailed test, a right-tailed test, or a two tailed test?
A) Left-tailed test
B) Two-tailed test
C) Right-tailed test

Quizplus · Accepted Answer

In a two-proportion hypothesis test, the null hypothesis is typically that the two proportions are equal (i.e. the difference between them is 0). The alternative hypothesis is that the proportions are not equal (i.e. the difference between them is not 0). This means that it is a two-tailed test, since we are interested in differences in both directions.

The Following MINITAB Output Display Presents the Results of a Hypothesis