Time to Practice – Week Three

Complete both Part A and Part B below.

Part A

1.     What does the critical value represent? (2 points) The critical value represents a value an individual would assume the test at hand to produce if the null hypothesis were true. It is the statistic a person believes to find.

2.     Given the following information, would your decision be to reject or fail to reject the null hypothesis? Setting the level of significance at .05 for decision making, provide an explanation for your conclusion. (3 points)

a.     The null hypothesis that there is no relationship between the type of music a person listens to and his crime rate (p < .05).  Null hypothesis is rejected as p value is less than .05

b.     The null hypothesis that there is no relationship between the amount of coffee consumption and GPA (p = .62).  Since p=.62, which is more than .05 or greater we accept the null hypothesis.

c.     The null hypothesis that there is no relationship between the number of hours worked and level of job satisfaction (p = .51). since p=.51 greater than .05 accept null hypothesis.

3.     Why is it harder to find a significant outcome (all other things being equal) when the research hypothesis is being tested at the .01 rather than the .05 level of significance? (2 points) When the test is done at the .01 rather than .05 it produces a much small value set while .05 produces a larger one. This leads to the contradictory data which is quite larder in the research hypothesis and more likely.

Part B

Complete the following questions. Be specific and provide examples when relevant.

Cite any sources consistent with APA guidelines.

Question	Answer
What is a research question that you would like to answer? Write the null and research hypotheses. Would you use a one- or two-tailed test? Why? (3 points)	If the Health department is tasked with finding out the rate of lung cancer connected with smoking in the past year is it comparable to average rate past 50 years. Null hypothesis: No difference in last year and last 50 years. Research hypothesis: there is a difference in last year and last 50 years. Using a two-tailed test because of the research hypothesis would show that it was not equal
What do we mean when we say that a statistical result is significant? What is the difference between a statistically significant and a meaningful result? Why is statistical significance important?  (4 points)	Significant means that there is a rate of certain probability in something. Meaningful results state that the results are valid and statically significant which means a person rejects the null hypothesis. With there being some probable difference between the results we can conclude the null hypothesis is not acceptable and should be rejected.

From Salkind (2011). Copyright © 2012 SAGE. All Rights Reserved.