# Exam 3 Study Guide: Chapters 12-17

1. Interpret the graph. Then construct a confidence interval from the information given. The critical values for a t and z distribution are given, but you'll need to know which one to use. This is like homework 15.
2. Know the concept that is fundamental to all hypotheses testing.
3. The summary statistics for a sample are given. Find the margin of error, the confidence interval, and then make a conclusion based on the confidence interval. Look at homework 14.
4. Write the claim symbolically. These are mathematical statements like "the average adult earns \$35,000 a year". They could be about one or two proportions or means. If there are two samples, be sure to define the subscripts or use subscripts that make sense. Eight parts.
5. Five statements are given. For each one, decide whether the statement is the null or alternative hypothesis.
6. Five critical value(s) and test statistics are given. For each case, decide whether it is a left tail, right tail, or two tail test and whether to Reject H0 or Retain H0.
7. A graph of a probability distribution is given along with a critical value and level of significance. Draw and label a vertical line at the critical value, shade and label the critical region, label the non-critical region, label each region with the area in that region, write "Reject H0" and "Retain H0" in the appropriate regions of the graph. Also, identify whether it is a left tail, right tail, or two-tail test. Most of this is in your notes and the graphs from the activities.
8. A joint frequency table is given. Use it to answer the probabilities of certain events occurring. Leave your answers in fraction form. A test statistic, p-value, and significance level are given. Read through some statements and decide which are true and which are false.
9. A confidence interval for the population proportion is given. Find the sample proportion and the margin of error.
10. Four conclusions are given. Properly word them. They are all of the form "Based on a p-value of ____ there ( is / is not ) enough evidence to ( reject / support ) the claim that ..."
11. Three confidence intervals are given along with a null hypothesis. Decide whether the test is left tailed, right tailed, or two tailed and whether you would reject or retain the null hypothesis.
12. Find the probabilities of multiple events happening. Use the multiplication rule. Three parts. This is like the second half of homework 7.
13. The output from a hypothesis test with Minitab is given. Interpret the results. Be able to determine the values of the summary statistics when the variable is transformed.
14. The output from a hypothesis test in Minitab is given. Interpret the results.

## Notes

• The formulas for the standard errors of the mean and proportion are given on the exam. The formula for the margin of error is given on the exam. The formula for the shortcut to finding the variation is given on the test. SS(x) = ∑x2-(∑x)2/n. You will need to know when to use the formulas, however. You will need to know the formula for the test statistic: TS = (observed-expected)/spread
• Where p-values are given, pay attention to whether they are for a one tail test or a two tail test. You may need to adjust the value depending on what type of value you have.
• You will not need the statistical tables or the computer during the exam.
• There is a take home exam with 6 problems. It is due at the beginning of class on the day of the exam.
• You may want to review the hypothesis testing assessment.

## Points per problem

 # Pts 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Take Home Total 10 3 6 16 5 10 7 16 4 12 6 6 13 6 30 150