Assignment: Steps to Hypotheses Testing

Instructions

For this Assignment, review this week's Learning Resources, including the 5 step approach to hypothesis testing document. Read the research scenario, below, and then answer the questions related to the steps that must be followed to make the appropriate decision as to reject or fail to reject the null hypothesis.

Research Scenario

Diastolic blood pressure (DBP) measurements from the general population form a normal distribution with a m = 82 mmHg and s = 10 mmHg. Epidemiological studies have shown that smoking is a contributing factor to high DBP. Using data from a cohort study, a researcher obtained a sample of n = 100 smokers whose average DBP was x¯ = 90. Do these data indicate that smoking is associated with significantly higher DBP in this sample? Test with alpha=.05.

Note
µ = population mean
x¯ = sample mean
s = standard deviation

Note: Each response is worth 6 points

Step 1: Set up your hypothesis and determine the level of significance

State the null hypothesis

1. In written format

2. In mathematical format

State the alternative hypothesis

3. In written format

-Continued below-

4. In mathematical format

Determine the Level of significance

5. Based on information in the scenario, what is the level of significance to be used?

Step 2: Select the appropriate test statistic

6. The appropriate test statistic for the above scenario is the one-sample z test. What is a Z test? Describe why this is the appropriate test for the scenario?

Step 3: Set up the decision rule

7. Based on the level of significance you set in Step 1 (Question 5) and whether your alternative hypothesis is directional or non-directional, what is your decision rule? (In other words, what is your rejection region?)

Step 4: Compute the test statistic

8. Calculate the z statistic. Please show your work.

Step 5: Conclusion

9. Do you reject or fail to reject the null hypothesis?

10. Is DBP affected by smoking in this sample?