Question

A researcher is interested in understanding the effects of type of therapy (CBT vs. family-based) and level of motivation (low vs. high) on treatment success rates in adolescents. The graphs below depict possible outcomes. NOTE: If the graphs (x2) do not show up, please email me. For the graph below (Graph 1), answer the following questions: (6) 9 7 Treatment success 2. 1 0 CBT Family-based Low High a. Is the main effect of type of therapy significant? (yes or no) b. Is the main effect of level of motivation significant? (yes or no) c. Is the interaction significant? (yes or no) d. Based on your answers above, explain the results For the graph below (GRAPH 2), answer the following questions: (5) 14 12 10 8 Treatment success 6 4 2 0 CBT Family-based Low High a. Is the main effect of type of therapy significant? (yes or no) b. Is the main effect of level of motivation significant? (yes or no) c. Is the interaction significant? (yes or no) d. Based on your answers above, explain the results

Answer 1

1.

A. No

Main effect can calculated by comparing mean scores of each level of single Variable. So here first independent variable is types of therapy-

Mean of the scores of CBT ( high and low scores at orange line)= (8+2)/2

= 10/2= 5

Mean of scores of family based therapy (high and low scores of blue line)= (8+2)/2

= 10/2= 5

Both the mean scores are same it means there is no main effect of types of the

Main effect can calculated by comparing mean scores of each level of single Variable. So here first independent variable is types of therapy-

Mean of the scores of CBT ( high and low scores at orange line)= (8+2)/2

= 10/2= 5

Mean of scores of family based therapy (high and low scores of blue line)= (8+2)/2

= 10/2= 5

Both the mean scores are same it means there is no main effect of types of therapies.

rapies.

B. No

To calculate main effect of level of motivation

Mean score of low motivation ( scores of orange and blue lines from left side)= (8+2)/2

= 10/2

= 5

Mean score of high motivation ( scores of orange and blue lines from the right side) = (8+2)/2

=10/2

= 5

Both the mean scores are same it means there is no significant main effect of levels of motivation on treatment success in adolescents.

C. Yes because both the lines are intersecting to each other it means there is significant interaction of both therapies.

D. This result shows that both therapies CBT and family based can not influence treatment but interaction of both therapies is effective for the treatment success in adolescents.

2.

A. Yes

Main effect can calculated by comparing mean scores of each level of single Variable. So here first independent variable is types of therapy-

Mean of the scores of CBT ( high and low scores at orange line)= (6+12)/2

= 18/2= 9

Mean of scores of family based therapy (high and low scores of blue line)= (1+7)/2

= 8/2= 4

There is a difference between the mean scores of both therapies it means there is significant main effect of types of therapies on the treatment success in adolescents.

B. Yes

To calculate main effect of level of motivation

Mean score of low motivation ( scores of orange and blue lines from left side)= (1+6)/2

= 7/2

= 3.5

Mean score of high motivation ( scores of orange and blue lines from the right side) = (7+12)/2

=19/2

= 9.5

There is difference between the mean scores of high and low levels of motivation it means there is significant main effect of levels of motivation on treatment success in adolescents.

C. No because both the lines are not intersecting to each other but they are parallel to each other it means there is no significant interaction.

D. This result shows that both the therapies CBT and family based therapy are effective for treatment success in adolescents but interaction of both therapies is not effective for treatment success in adolescents or we can say there is no significant influence of interaction of both therapies.