# Exercise 31

Pages: 3 (929 words) Published: November 27, 2012
1. What are the two groups whose results are reflected by the t ratios in Tables 2 and 3? The two groups are pre-test and 3-month measures and pre-test and 6-month measures.

2. Which t ratio in Table 2 represents the greatest relative or standardized difference between the pretest and 3 months outcomes? Is this t ratio statistically significant? Provide a rationale for your answer. The t ratio for Total risk score represents the greatest relative or standardized difference between the pre-test and 3 months outcomes because the value of t test statistics is bigger than any other group. This ratio is statistically significant because the p-value corresponding to this group is less than 0.05.

3. Which t ratio listed in Table 3 represents the smallest relative difference between the pretest and 3 months? Is this t ratio statistically significant? What does this result mean? The t ratio for Stress management the smallest relative difference between the pre-test and 3 months because the values of t test statistics is smaller than any other group. This ratio is not statistically significant because here the p-value is bigger than 0.05. This result depicts that there is no significant difference in the stress management at pre-test and after 3 months. Stress management is same at pre-test and at 3 months.

4. What are the assumptions for conducting a t-test for dependent groups in a study? Which of these assumptions do you think were met by this study? The assumptions for conducting a t-test for dependent groups in a study are the data for both group should be normally distributed and the groups are correlated with each other. The groups are correlated because the same measurement is taken over from the same subject at pre-test, 3 months and at 6 months. There are 25 subjects in this study and out of 25, 21 have completed the study, it means that the data is enough to conduct the paired sample t test. Also the data should be continuous and this...