Question

Use the Paired Samples T Test function in SPSS to answer each of the following questions. (Assume a nondirectional research hypothesis and a critical level of significance of.05) A study was conducted on the use of family therapy as a treatment for anorexia. The study included 17 girls who were weighed before and after treatment. The weights of the girls, in pounds, are given below. Before 83.80 83.30 86.00 82.50 86.70 79.60 76.90 94.20 73.40 80.50 81.60 82.10 77.60 83.50 89.90 86.00 87.30 After 95.20 94.30 91.50 91.90 100.30 76.70 76.80 101.60 94.90 75.20 77.80 95.50 90.70 92.50 93.80 91.70 98.00

1. How would you explain the procedure for determining the degrees of freedom for a T Test for Dependent Means?

2. What is the value of the degrees of freedom that is reported in the output?

3. Does this correspond to the value obtained using the formula for the degrees of freedom?

4. Based on the results of the T Test for Dependent Means, what would you conclude about the effects of family therapy on weight increase for girls with anorexia.

5. Write a statement as it might appear in an article that reports the results of the TTest for Dependent Means.

Answer 1

The number of degrees for a t test for dependent means is number of pairs minus one, therefore, it will be 17 - 1 = 16 2. The output from Excel for dependent samples test is: The degrees of freedom from output is 16. 3. Yes, the degrees of freedom obtained from output is same as the degrees of freedom obtained from formula. 4. Since, the p-value for the $poundsectionpound(0.0003) is less than the level of significance, we will conclude about the effects of family therapy on weight increase for girls with anorexia. 5. The result from the t test suggest that after applying the treatment for anorexia the weights of the girls increase.