Your Name __________________________________



Psychology 201W, Spring 2002


Dr. John A. Johnson

Lab assignment #9 - Graphing and interpreting results in factorial designs (Due in lab Friday, April 12)

This lab is worth 30 points.

1. A researcher is interested in influences on altruism. He conducts an experiment in which an individual solicits money from pedestrians at a busy intersection. One independent variable is the way the person soliciting money is dressed: well-dressed or poorly-dressed. A second independent variable is whether the money is supposedly collected for a charitable organization (i.e., "canning") or for the individual's own use ("panhandling"). The dependent variable is the average amount of money given. Here are the results:


poorly dressed


collecting for self

$ .30

$ .30

collecting for charity

$ .15

    1. Graph the results (be sure to label the graph appropriately): (3 points)



    3. Describe in sentences the effects that are present (5 points)



    5. Explain WHY the results might have turned out as they did (2 points)


2. A researcher was interested in conformity to social pressure, and conducted an experiment in which subjects received social pressure to agree with ideas expressed in a videotaped speech. She expected greater conformity to unfamiliar ideas, and greater conformity in the context of larger groups. The independent variables were thus (a) familiar vs. unfamiliar ideas, and (b) group size of 2 or 7. The dependent variable was rated agreement with the presented idea, measured on a scale from 1 to 5 (where 1 indicates strong disagreement and 5 indicates strong agreement). The results were as follows:


2-person group

7-person group 

familiar idea 



unfamiliar idea



The researcher also conducted an analysis of variance to test the significance of these results. The F values and their significance levels are listed below:







idea type



group size



idea x group




    1. Graph the results (be sure to label the graph appropriately): (3 points)



    3. Describe the results (in sentences): (5 points)


3. A computer manufacturer must decide whether to include an expensive program with all new computers sold. The program provides "on-line" help (presented on the computer screen). The alternative is to develop a new printed manual to provide the same kind of help. The manufacturer hypothesizes that which kind of help is preferred might depend on whether the user is a computer expert or a computer novice, and designs an experiment in which expert or novice computer users work with the new computer, using either the manual or the "on-line" help system. Both variables will be manipulated between subjects. Answer the following questions about this experiment:

    1. What could the manufacturer use as a dependent variable? (2 points)



    3. Describe the design of the manufacturer's experiment: (3 points)



    5. The description of the manufacturer's hypothesis given above is ambiguous. Describe one specific hypothesis that fits the description: (4 points)



    7. Draw a graph that illustrates the expected results, given the hypothesis you listed in (c) [be sure to label the graph appropriately]: (3 points)