Preliminary Edition Of Statistics Learning From Data 1st Edition By Roxy Peck – Test Bank
Chapter 11: Asking and Answering Questions about
the Difference Between Two Population Proportions
The following questions are in a True / False format. The answers to these questions will
frequently depend on remembering facts, understanding of the concepts, and knowing the
statistical vocabulary. Before answering these questions, be sure to read them carefully!
T F 1. The formula for the standard error of 1 2 p p ˆ ˆ − used in hypothesis testing
and confidence intervals is the same.
T F 2. The large sample confidence interval procedure for estimating
1 2 p p − using z can safely be used if the combined samples have at least 20
“successes” and 20 “failures.”
T F 3. The large sample confidence interval procedure for estimating
1 2 p p − requires the random samples to be selected independently.
T F 4. When testing the hypothesis 1 2 : 0 Hp p o − = , the alternative hypotheses
1 2 : 0 Hpp a − > and 2 1 : 0 Hp p a − > can be used interchangeably.
T F 5. When testing the hypothesis 1 2 : 0 Hp p o − = , a test statistic near zero
indicates strong support for the null hypothesis.
T F 6. A 95% confidence interval for 1 2 p p − is wider than a 90% confidence
interval constructed using the same sample data.
T F 7. If the P-value in a test of 1 2 : 0 Hp p o − = is 0.014, you would reject the
null hypothesis at the 0.01 significance level.
T F 8. If the P-value in a test of 1 2 : 0 Hp p o − = is 0.578, you have strong
evidence that the null hypothesis is true.
T F 9. If the P-value in a test of 1 2 : 0 Hp p o − = is 0.0005, you have strong
evidence that the null hypothesis is false.
T F 10. If the confidence interval for 1 2 p p − does not contain 0, it is plausible
that 1 2 p p = .