Guide to using the learning objectives
1.
Define^{1
}factorial experiment. Contrast^{4} factorial
experiments with the multiplegroup experiments discussed in Chapter 11.
2.
Produce^{5
}a 2 x 2 factorial experiment studying the
effects of chocolate consumption and listening to music on test performance.
3.
Compare^{4
}and contrast^{4} your 2 X 2 factorial experiment with
a. An experiment that examines four levels
of a single independent variable (e.g., four levels of chocolate consumption).
b. Four simple experiments.
4.
Explain^{2}how
your 2 x 2 factorial experiment could yield each of the following:
a.
four
simple main effects;
b.
two
overall main effects (in your explanation,
(a) define^{1}main effect and (b) explain^{2 }how overall main
effects can be estimated from simple main effects); and
c. an interaction (in your explanation,
(a) define^{1} interaction and (b) explain how the
interaction can be estimated from simple main effects).
5.
Describe,^{1}in your own words, what an interaction is.
Produce^{5} an example of an interaction. Describe^{2} the
relationship between interactions and moderating variables. Describe^{2}
the relationship between interactions and external validity. Explain^{2}
why psychologists are interested in interactions.
6.
Using
the discussion in this chapter as an example, outline^{3} the questions
you could answer with the 2 x 2 factorial experiment you generated to study the
effects of chocolate consumption and listening to music on test performance.
7.
Distinguish^{4}between
a main effect and an interaction. Explain^{2} how you could have an
interaction without a main effect.
8.
Produce^{5}a
list of the eight different patterns of results you could get from a 2 x
2factorial experiment. Using your 2 x 2 experiment on chocolate consumption, listening
to music, and test performance as your example, illustrate^{3 }(using
either graphs or tables of hypothetical data) how your results could lead to
each of these eight potential patterns.
9.
Suppose
that you conduct your experiment on chocolate consumption, listening to music, and
test performance. Distinguish^{4}between
the conclusions you would draw if you obtained a main effect for chocolate
consumption but no interaction versus if you obtained a main effect for
chocolate consumption and an interaction.
10.
Suppose
you expand your experiment to include three levels of chocolate consumption. You
have 36 participants. Compute^{3} the missing values for the table below.
Source of
Variance 
Sum of
Squares 
df 
MS 
F 
Chocolate
consumption main effect 
8 



Listening
to music main effect 
6 



Interaction
between chocolate consumption and listening to music 
20 



Error
Term 
60 



Total 



11.
Distinguish^{4}between
ordinal and disordinal interactions. Explain^{2}
why ordinal interactions may be the result of having ordinal data.
12.
Imagine
that a simple (twogroup) experiment finds that students taking a psychology test
printed on blue paper do better than students taking the same test printed on
white paper. Expand on this simple experiment by generating^{5} a 2X 2
factorial experiment that includes a replication factor. Justify^{6}why
your 2 X 2 experiment has more external validity than the simple experiment had.
13.
Devise^{5}a
factorial experiment by adding a potential moderating variable to a simple experiment
(you may use the simple experiment referred to in the previous objective).
Describe^{2}, using the terms main effects and interaction, a pattern
of results that would support the idea that you found a moderating variable. Explain^{2 }the value of finding
a moderator factor.
14.
Explain^{2}how
an interaction may indicate the effect of similarity.
15.
Describe^{2}the
main limitation of using a nonexperimental variable
in a study.
16.
Propose^{5}and
justify^{6} expanding the simple experiment discussed in Objective13
into a 2 X 2 factorial design by
a. Adding a nonexperimental
variable to increase the generalizability of the
findings
b. Adding a nonexperimental
variable to increase the power of the design
c. Adding a moderating factor