Chapter 9: Q .1. (page 563)
No homework? Mr. Tabor believes that less than of the students at his school completed their math homework last night. The math teachers inspect the homework assignments from a random sample of students at the school.
Chapter 9: Q .1. (page 563)
No homework? Mr. Tabor believes that less than of the students at his school completed their math homework last night. The math teachers inspect the homework assignments from a random sample of students at the school.
All the tools & learning materials you need for study success - in one app.
Get started for free
Better parking A local high school makes a change that should improve student
satisfaction with the parking situation. Before the change, of the school’s students approved of the parking that was provided. After the change, the principal surveys an SRS of from the more than students at the school. In all, students say that they approve of the new parking arrangement. The principal cites this as evidence that the change was effective.
a. Describe a Type I error and a Type II error in this setting, and give a possible
consequence of each.
b. Is there convincing evidence that the principal’s claim is true?
The standardized test statistic for a test of versus isThis test is
a. not significant at either or
b. significant at but not at
c. significant atbut not at
d. significant at both and
e. inconclusive because we don’t know the value of
Explaining confidence: Here is an explanation from a newspaper concerning one of its opinion polls. Explain what is wrong with the following statement.
For a poll of adults, the variation due to sampling error is no more than
percentage points either way. The error margin is said to be valid at the
confidence level. This means that, if the same questions were repeated in polls, the results of at least surveys would be within percentage points of the results of this survey.
Error probabilities and power You read that a significance test at the
significance level has probability of making a Type II error when a specific alternative is true.
a. What is the power of the test against this alternative?
b. What’s the probability of making a Type I error?
Which of the following confidence intervals would lead us to reject in favor of at the significance level?
a.
b.
c.
d.
e. None of these
What do you think about this solution?
We value your feedback to improve our textbook solutions.