effects of study
Name: ______________________ Psych 100
Hypothesis Testing and Critical Evaluations #2
1. A total of 100 undergraduates were recruited to participate in a study on the effects of study location on learning. The study employed a 2 x 2 between-subjects design, with all participants studying a chapter on the science of gravity and then being tested on the to-be-learned material one week later. Fifty of the participants were asked to study the chapter at the library, whereas the other fifty were asked to study the chapter at home. As a separate manipulation, participants were either told to study the chapter for 30 min or 120 min. The hypothetical set of data shown below represents the level of performance of participants on the test as a function of condition.
30 min 120 min Library 60 80 Home 40 60
a) Is there a main effect of Study Location? In answering, provide the marginal means and state the direction of the effect (if there is one).
b) Is there a main effect of Study Duration? In answering, provide the marginal means and state the direction of the effect (if there is one).
c) Do the results indicate an interaction? If so, describe the nature of the interaction by
comparing the simple effects.
d) Illustrate the results with a bar graph using the figure provided.
0
20
40
60
80
100
30 min 120 min
Library
Home
e) Interpret the results. What do they tell you about how study location affects learning? (be
sure to refer to the interaction or lack thereof)
Name: ______________________ Psych 100
2. Now pretend that the following data were obtained:
30 min 120 min Library 50 90 Home 50 70
a) Is there a main effect of Study Location? In answering, provide the marginal means and state the direction of the effect (if there is one).
b) Is there a main effect of Study Duration? In answering, provide the marginal means and state the direction of the effect (if there is one).
c) Do the results indicate an interaction? If so, describe the nature of the interaction by
comparing the simple effects.
d) Illustrate the results with a bar graph using the figure provided.
0
20
40
60
80
100
30 min 120 min
Library
Home
e) Interpret the results. What do they tell you about how study location affects learning? (be
sure to refer to the interaction or lack thereof)
Name: ______________________ Psych 100
3. Now pretend that the following data were obtained:
30 min 120 min Library 50 90 Home 60 80
a) Is there a main effect of Study Location? In answering, provide the marginal means and state the direction of the effect (if there is one).
b) Is there a main effect of Study Duration? In answering, provide the marginal means and state the direction of the effect (if there is one).
c) Do the results indicate an interaction? If so, describe the nature of the interaction by
comparing the simple effects.
d) Illustrate the results with a bar graph using the figure provided.
0
20
40
60
80
100
30 min 120 min
Library
Home
e) Interpret the results. What do they tell you about how study location affects learning? (be
sure to refer to the interaction or lack thereof)
Name: ______________________ Psych 100
4. Now pretend that the following data were obtained:
30 min 120 min Library 95 95 Home 95 95
a) Is there a main effect of Study Location? In answering, provide the marginal means and state the direction of the effect (if there is one).
b) Is there a main effect of Study Duration? In answering, provide the marginal means and state the direction of the effect (if there is one).
c) Do the results indicate an interaction? If so, describe the nature of the interaction by
comparing the simple effects.
d) Illustrate the results with a bar graph using the figure provided.
0
20
40
60