## Exam 3 - Study Guide

1. Which distributions are symmetric about their mean? (multiple choice)
2. Which distributions require degrees of freedom? (multiple choice)
3. Which distribution should be used to find a confidence interval? (multiple choice)
4. Properties of the standard normal distribution. (multiple choice)
5. Properties of the Student's t distribution. (multiple choice)
6. Properties of the Chi-Square distribution (multiple choice)
7. How to change the maximum error of the estimate. (multiple choice)
8. When should a normal approximation to the binomial be used? (true false)
9. What are degrees of freedom? (true false)
10. What is the best point estimator for the population mean? (true false)
11. What is the best point estimator for the population variance? (true false)
12. What needs to be estimated? (true false)
13. Relationship between confidence level and area in tails. (true false)
14. Relationship between confidence level and confidence interval width. (true false)
15. Usage of the continuity correction factor. (true false)
16. Calculate a cutoff score for an exam when a grades are assigned by percentage of students, rather than quality of exam. Only one score to calculate. See problem 33 in section 5.3.
17. Calculate probabilities for a standard normal distribution. Also sketch the region. These are exactly out of the book. See problems 5 - 24 in section 5.2. Five parts.
18. Approximate a binomial probability using the normal distribution. See your notes for the problem we did in class about passing an exam with at least 60% of 100 true-false questions answered correctly.
19. Calculate a normal probability for an individual and also for the mean of a sample of people. This problem is exactly out of the text. Look at problems 1, 2, 17, and 18 in section 5.4 and problem 8 in the chapter 5 review.
20. Calculate a normal probability from a non-standard distribution. This problem is exactly out of the text. See problems 9 - 29 (odds) in section 5.3.
21. Summarize the Central Limit Theorem. The CLT has been stated with certain key words omitted. Fill in the blanks.
22. Calculate the degrees of freedom for a problem. This is to test your understanding of the concept of degrees of freedom, rather than the memorization of a formula.
23. Look up values from the tables using Critical Value notation. One normal, one student's t, and one chi-square. See explanation of critical value notation in section 6.2 (page 290) and section 6.4 (page 322).
24. Find the critical values for a confidence interval about the population variance. Find the sample size when the critical value is known.
Scoring
• Multiple choice questions are 4 points each (1 point for each possible answer).
• True-false questions are 2 points each.
• 16, 18, 19, 20, and 22 are 4 points for each part.
• 17 is 3 points per part for a total of 15 points.
• 21 is 6 points.
• 23 and 24 are 2 points per part.
Distributions we have discussed (and hence you should know the properties of)::
• Uniform (from statdisk)
• Binomial
• Normal
• Student's t
• Chi-Square
There is no working in groups on this exam.

The take home exam for chapter six is to work the even numbered problems from the Chapter 6 review on pages 331 - 333. There are nine problems, 2 points each, for a total of 18 points. This will be a separate grade from the chapter 5-6 exam which is worth 100 points.