Answers for EXERCISE 16 page 122 (Questions 1- 4 are optional)• Mean and Standard Deviation
Exercise 16: Mean and Standard Deviation
1. The researchers analyzed the data they collected as though it were at what level of measurement?
a. Nominal
b. Ordinal
c. Interval/ratio
d. Experimental
Answer: c. The researchers analyzed the data as though it were at the interval/ratio level since they calculated means (the measure of central tendency that is appropriate only for interval/ratio level data) and standard deviations (the measure of dispersion for interval/ratio data) to describe their study variables.
2. What was the mean posttest empowerment score for the control group? Answer: Mean = 97.12.
3. Compare the mean baseline and posttest depression scores of the experimental group. Was this an expected finding? Provide a rationale for your answer. Answers may vary. The experimental group subjects scored lower on the depression posttest (mean = 13.36 vs. the baseline score of mean = 14.00), meaning that they were less depressed after the completion of the empowerment program. This was an expected finding, because the researchers hypothesized that the empowerment program would be beneficial to ESRD patients and result in a decrease in their depression scores. However, the difference in the depression baseline and posttest means for the experimental group was only 0.64, which is less than what might have been expected.
4. Compare the mean baseline and posttest depression scores of the control group. Do these scores strengthen or weaken the validity of the research results? Provide a rationale for your answer.
Answer: The mean baseline and posttest depression scores of the control group were identical. Both means equaled 10.40, which indicates that there was no change in the level of depression of the control group subjects
