In: Statistics and Probability
Since an instant replay system for tennis was introduced at a major tournament, men challenged 1441 referee calls, with the result that 422 of the calls were overturned. Women challenged 758 referee calls, and 216 of the calls were overturned. Use a 0.05 significance level to test the claim that men and women have equal success in challenging calls. Complete parts (a) through (c) below.
a. Test the claim using a hypothesis test.
Consider the first sample to be the sample of male tennis players who challenged referee calls and the second sample to be the sample of female tennis players who challenged referee calls. What are the null and alternative hypotheses for the hypothesis test?
Identify the test statistic.
Identify the P-value.
What is the conclusion based on the hypothesis test?
The P-value is
(less than or greater than)
the significance level of
alpha =0.05, so
(reject OR fail to reject) the null hypothesis. There
(is sufficient OR is not sufficient)
evidence to warrant rejection of the claim that women and men have equal success in challenging calls.
b. Test the claim by constructing an appropriate confidence interval.
The
9595%
confidence interval is
nothingless than<left parenthesis p 1 minus p 2 right parenthesisp1−p2less than<nothing.
(Round to three decimal places as needed.)
What is the conclusion based on the confidence interval?
Because the confidence interval limits
(include OR do not include)
0, there
(does not OR does)
appear to be a significant difference between the two proportions. There
(is not sufficient OR is sufficient)
evidence to warrant rejection of the claim that men and women have equal success in challenging calls.
c. Based on the results, does it appear that men and women may have equal success in challenging calls?
A.
The confidence interval suggests that there is no significant difference between the success of men and women in challenging calls.
B.
The confidence interval suggests that there is a significant difference between the success of men and women in challenging calls. It is reasonable to speculate that women have more success.
C.
The confidence interval suggests that there is a significant difference between the success of men and women in challenging calls. It is reasonable to speculate that men have more success.
D.
There is not enough information to reach a conclusion.
using excel>addin>phstat<two sample test >z test for difference
we have
Z Test for Differences in Two Proportions | ||||
Data | Confidence Interval Estimate | |||
Hypothesized Difference | 0 | of the Difference Between Two Proportions | ||
Level of Significance | 0.05 | |||
Group 1 | Data | |||
Number of Items of Interest | 422 | Confidence Level | 95% | |
Sample Size | 1441 | |||
Group 2 | Intermediate Calculations | |||
Number of Items of Interest | 216 | Z Value | -1.9600 | |
Sample Size | 758 | Std. Error of the Diff. between two Proportions | 0.0203 | |
Interval Half Width | 0.0398 | |||
Intermediate Calculations | ||||
Group 1 Proportion | 0.292852186 | Confidence Interval | ||
Group 2 Proportion | 0.284960422 | Interval Lower Limit | -0.0319 | |
Difference in Two Proportions | 0.007891764 | Interval Upper Limit | 0.0477 | |
Average Proportion | 0.2901 | |||
Z Test Statistic | 0.3876 | |||
Two-Tail Test | ||||
Lower Critical Value | -1.9600 | |||
Upper Critical Value | 1.9600 | |||
p-Value | 0.6983 | |||
Do not reject the null hypothesis |
a. the null and alternative hypotheses for the hypothesis test
Ho:p1=p2
HA:p1 p2
the test statistic is 0.3876
the P-value is 0.3876
What is the conclusion based on the hypothesis test?
The P-value is greater than the significance level of alpha =0.05, so fail to reject the null hypothesis. There is not sufficient evidence to warrant rejection of the claim that women and men have equal success in challenging calls.
b. Test the claim by constructing an appropriate confidence interval.
The 95% confidence interval is -0.0319<p 1 - p 2<0.048
What is the conclusion based on the confidence interval?
Because the confidence interval limits include 0, there does not appear to be a significant difference between the two proportions. There is not sufficient evidence to warrant rejection of the claim that men and women have equal success in challenging calls.
c. Based on the results, does it appear that men and women may have equal success in challenging calls?
A.The confidence interval suggests that there is no significant difference between the success of men and women in challenging calls.