02 Feb Exercise 26: Determining the

Statistics for Nursing Research: A Workbook for Evidence-Based Practice, 2nd Edition

Exercise 26: Determining the Normality of a Distribution

Questions to Be Graded

Name:______________________________________ Class: ______________________

Date: ___________________________________________________________________

To answer a question, please click on “Choose an item” and on the drop-down arrow and choose an answer. Here is a resulting drop-down list:

If it is not working, you can enter your answers to the table at the end of the file.

Please include your SPSS output following each question or before the grading table at the end of the file.

The following questions refer to the section called “Data for Additional Computational Practice” in Exercise 26 of Grove & Cipher, 2017.

1. Plot the frequency distribution for “Age at Enrollment” by hand or by using SPSS.

Please attach a graph at the end of the file. You can copy the graph from SPSS or draw by hand then take a picture of it and insert to this file.

A. Included.

B. Not included.

Answer: Choose an item.

2. How would you characterize the skewness of the distribution in Question 1—positively skewed, negatively skewed, or approximately normal? Provide a rationale for your answer.

A. Positively skewed, as evidenced by the “tail” of the distribution appearing above the mean. The distribution is shifted to the left with the largest portion of data being below the mean.

B. Negatively skewed, as evidenced by the “tail” of the distribution appearing below the mean. The distribution is shifted to the right with the largest portion of data being above the mean.

C. Approximately normal, because the distribution is symmetric and bell-shaped.

Answer: Choose an item.

3. Compare the original skewness statistic and Shapiro-Wilk statistic with those of the smaller dataset (n = 15) for the variable “Age at First Arrest.” How did the statistics change?

A. The skewness statistic was reduced and the Shapiro-Wilk statistic was no significant at the significance level of 0.05.

B. The skewness statistic was increased and the Shapiro-Wilk statistic was significant at the significance level of 0.05.

C. The skewness statistic remained the same.

Answer: Choose an item.

and how would you explain these differences or no differences?

A. It appears that by deleting the first five values, the frequency distri­bution became more symmetrical and less skewed, thereby yielding a nonsignificant test of normality.

B. It appears that by deleting the first five values, the frequency distri­bution became less symmetrical and more skewed, thereby yielding a significant test of normality.

C. The deletion of the first five values did not make any differences.

Answer: Choose an item.

4. Plot the frequency distribution for “Years of Education” by hand or by using SPSS.

Please attach a graph at the end of the file.

A. Attached.

B. Not attached.

Answer: Choose an item.

5. How would you characterize the kurtosis of the distribution in Question 4—leptokurtic, mesokurtic, or platykurtic? Provide a rationale for your answer.

A. Leptodurtic, as evidenced by the peakedness of the distribution and the limited variance of the values.

B. Mesokurtic, as evidenced by an intermediate degree of kurtosis.

C. Platykurtic, as evidenced by a relatively flat distribution and largest variance.

Answer: Choose an item.

6. What is the skewness statistic for “Age at Enrollment”? How would you characterize the magnitude of the skewness statistic for “Age at Enrollment”?

A. 0.622. Because the absolute value is less than 1.0, the magnitude is not thought to reveal substantive skewness.

B. -0.622. Because the absolute value is less than 1.0, the magnitude is not thought to reveal substantive skewness.

C. 1.523. Because the absolute value is greater than 1.0, the magnitude is thought to reveal substantive skewness.

D. -1.523. Because the absolute value is less than 1.0, the magnitude is not thought to reveal substantive skewness.

Answer: Choose an item.

7. What is the kurtosis statistic for “Years of Education”? How would you characterize the magnitude of the kurtosis statistic for “Years of Education”?

A. 0.936. It is not significant different from 0 so the magnitude is not thought to reveal substantive kurtosis.

B. -0.936. It is not significant different from 0 so the magnitude is not thought to reveal substantive skewness.

C. 1.251. Because the absolute value is greater than 1.0, the magnitude is thought to reveal substantive skewness.

D. -1.251. Because the absolute value is less than 1.0, the magnitude is not thought to reveal substantive skewness.

Answer: Choose an item.

8. Using SPSS, compute the Shapiro-Wilk statistic for “Number of Times Fired from Job.” What would you conclude from the results?

A. The statistic was significant at p = 0.001, indicating that the distribution for Number of Times Fired significantly deviated from normality.

B. The statistic was not significant at p = 0.05, indicating that the distribution for Number of Times Fired did not significantly deviate from normality.

C. I could not do this test.

Answer: Choose an item.

9. In the SPSS output table titled “Tests of Normality,” the Shapiro-Wilk statistic is reported along with the Kolmogorov-Smirnov statistic. Why is the Kolmogorov-Smirnov statistic inappropriate to report for these example data?

Is the following statement true or false?

The Kolmogorov-Smirnov statistic is appropriate to report for large samples, usually greater than n = 2000. Because the example sample size is small (n = 15), the Shapiro-Wilk statistic is the more appropriate test of normality.

A. True

B. False

Answer: Choose an item.

10. How would you explain the skewness statistic for a particular frequency distribution being low and the Shapiro-Wilk statistic still being significant at p < 0.05? A. It is common, because the Shapiro-Wilk test examines the entire shape of the distribution, while the skewness statistic examines only skewness and asymmetry. B. It is common, because the Shapiro-Wilk test examines the average of the two tails of the distribution, while the skewness statistic examines only skewness and asymmetry at one side. Answer: Choose an item. SPSS Outputs If you like to include some SPSS outputs, please add here. Grading Please do not add or delete a row or column for the following grading table. If you have a problem with the drop-down lists, then you can enter your answers in the second column. If you use the drop-down lists, the instructor will update your answers in the table. Thanks Question Your answer Correct answer Possible points Your points 1 9 2 4.5 3 4.5 3 9 4 9 5 9 6 9 7 9 8 9 9 9 10 9 Total 90