III. The P -value for the test statistic in this situation will be larger for 11 degrees of freedom than
for 25 degrees of freedom.
a. I only
b. II only
c. III only
d. I and II only
e. I, II, and III
When is it OK to use a confidence interval instead of computing a P -value in a hypothesis test?
a. In any significance test
b. In any hypothesis test with a two-sided alternative hypothesis
c. Only when the hypothesized value of the parameter is not in the confidence interval
d. Only when you are conducting a hypothesis test with a one-sided alternative
e. Only when doing a test for a single population mean or a single population proportion
Which of the following is not a required step for a significance test?
a. State null and alternative hypotheses in the context of the problem.
b. Identify the test to be used and justify the conditions for using it.
c. State the significance level for which you will decide to reject the null hypothesis.
d. Compute the value of the test statistic and the P- value.
e. State a correct conclusion in the context of the problem.
Which of the following best describes what we mean when say that t -procedures are robust?
a. The t -procedures work well with almost any distribution.
b. The numerical value of t is not affected by outliers.
c. The t -procedures will still work reasonably well even if the assumption of normality is violated.
d. t -procedures can be used as long as the sample size is at least 40.
e. t -procedures are as accurate as z -procedures.
For a hypothesis test of H 0 : μ = μ 0 against the alternative H (^) A : μ < μ 0 , the z -test statistic is found
to be 2.00. This finding is
a. significant at the 0.05 level but not at the 0.0l level.
b. significant at the 0.01 level but not at the 0.05 level.
c. significant at both the 0.01 and the 0.05 levels.
d. significant at neither the 0.01 nor the 0.05 levels.
e. not large enough to be considered significant.
Two types of tennis balls were tested to determine which one goes faster on a serve. Eight different
players served one of each type of ball and the results were recorded: