Preparing for the next class
In the next class, you will need to know all the steps needed to complete a hypothesis test for a population mean, which are similar to the steps for a hypothesis test for a population proportion.
Questions 1–8: Researchers want to examine the effect of diet on cholesterol level. They select a random sample of 125 adult males who are vegetarians and test their cholesterol levels to determine if they are significantly different from 201.5 milligrams of cholesterol per deciliter (mg/dl), which is the average cholesterol level of all adult males without heart disease. The results are shown in the following table:
| Size | Mean | Standard Deviation | |
| Sample | 125 | 183.4 mg/dl | 15 |
Question 1
1) How would you write the null hypothesis?
a) [latex]H_{0}:\mu>201.5[/latex]
b) [latex]H_{0}:\mu<201.5[/latex] c) [latex]H_{0}:\mu=201.5[/latex] d) [latex]H_{0}:\mu\neq201.5[/latex]
Question 2
2) How would you write the alternative hypothesis?
a) [latex]H_{A}:\mu>201.5[/latex]
b) [latex]H_{A}:\mu<201.5[/latex] c) [latex]H_{A}:\mu=201.5[/latex] d) [latex]H_{A}:\mu\neq201.5[/latex]
Question 3
3) In this scenario, is the alternative hypothesis one-tailed or two-tailed?
a) One-tailed
b) Two-tailed
Question 4
4) What data will be used for the hypothesis test?
a) Data about all U.S. men
b) No data are needed.
c) Sample data about cholesterol levels for a random sample of 125 men
Question 5
5) What conditions were met for this statistical test?
a) The sample size is large enough.
b) The sample is random from the population of interest.
c) Both a and c
Question 6
6) After writing the null and alternative hypotheses, collecting sample data, and checking test assumptions, what is the next step in hypothesis testing?
a) Calculate a P-value.
b) Interpret the results of the test in context.
c) Calculate the value of a test statistic.
Question 7
7) After calculating a test statistic, what is the next step in hypothesis testing?
a) Calculate a P-value.
b) Interpret the results of the test in context.
c) Calculate the value of a test statistic.
Question 8
8) What is the final step in hypothesis testing?
a) Calculate a P-value.
b) Interpret the results of the test in context.
c) Calculate the value of a test statistic.
