# State the research hypothesis and null hypothesis

**Provide **a response to the following prompts.

*Note:* Each team member should compute the following questions and submit them to the Learning Team forum. The team should then discuss each team member’s answers to ascertain the correct answer for each question. Once your team has answered all the questions, submit a finalized team worksheet.

1. When a result is not extreme enough to reject the null hypothesis, explain why it is wrong to conclude that your result supports the null hypothesis.

2. List the five steps of hypothesis testing and explain the procedure and logic of each.

3. A researcher wants to know whether people who regularly listen to radio talk shows are more or less likely to vote in national elections than people in general.

a. State the research hypothesis and null hypothesis

b. Would the researchers use a one- or two-tailed *Z* test?

4. The general population (Population 2) has a mean of 30 and a standard deviation of 5, and the cutoff *Z* score for significance in a study involving one participant is 1.96. If the raw score obtained by the participant is 45, what decisions should be made about the null and research hypotheses?

5. One hundred people are included in a study in which they are compared to a known population that has a mean of 73, a standard deviation of 20, and a rectangular distribution.

a. μM = __________.

b. σM = __________.

c. The shape of the comparison distribution is __________.

d. If the sample mean is 75, the lower limit for the 99% confidence interval is __________.

e. If the sample mean is 75, the upper limit for the 99% confidence interval is __________.

f. If the sample mean is 75, the lower limit for the 95% confidence interval is __________.

g. If the sample mean is 75, the upper limit for the 95% confidence interval is __________.

6. A psychology professor of a large class became curious as to whether the students who turned in tests first scored differently from the overall mean on the test. The overall mean score on the test was 75 with a standard deviation of 10; the scores were approximately normally distributed. The mean score for the first 20 students to turn in tests was 78. Using the .05 significance level, was the average test score earned by the first 20 students to turn in their tests significantly different from the overall mean?

1. Use the five steps of hypothesis testing.

2. Figure the confidence limits for the 95% confidence interval.