Week 3 Practice Worksheet

University of Phoenix Material

Week 3 Practice Worksheet

Prepare a written response to the following questions. Each correct answer is worth one point unless otherwise noted. Week 3 Practice Worksheet is worth 20 points.

Chapter 7

1. List the four steps of hypothesis testing, and explain the procedure and logic of each.

Step 1:      

Step 2:      

Step 3:      

Step 4:      

2. Based on the information given for the following studies, decide whether to reject the null hypothesis or fail to reject the null hypothesis. In the Conclusion column, type either “Reject” or “Fail to Reject.” Assume that all populations are normally distributed. For each, give:

a. The Z-score cutoff (or cutoffs) on the comparison distribution at which the null hypothesis should be rejected.

b. The Z-score on the comparison distribution for the sample score.

c. Your conclusion.

Study	µ	σ	Sample Score	p	Tails of Tests
A	5	1	7	0.05	1 (high predicted)
B	5	1	7	0.05	2
C	5	1	7	0.01	1 (High predicted)
D	5	1	7	0.01	2

Problem	Cutoff Score	Z Score	Conclusion
A
B
C
D

a. 3. A researcher predicts that listening to music while solving math problems will make a particular brain area more active. To test this, a research participant has her brain scanned while listening to music and solving math problems, and the brain area of interest has a percentage signal change of 58. From many previous studies with this same math problem’s procedure (but not listening to music), it is known that the signal change in this brain is normally distributed with a mean of 35 and a standard deviation of 10.

b. Using the .01 level, what should the researcher conclude? Solve this problem by stating the cutoff score, the z score, and the decision based upon the calculated results.

Cutoff score =      

Z Score =      

Conclusion:      

Explain your answer to someone who has never had a course in statistics (but who is familiar with mean, standard deviation, and Z scores).