Statistics for the Behavioral Sciences by Frederick J. Gravetter, Larry B. Wallnau ISBN 10: 1305504917 ISBN 13: 9781305504912

PREVIEW
There is some evidence that people with a visible tattoo
are viewed more negatively than are people without
a visible tattoo (Resenhoeft, Villa, and Wiseman,
2008). In the study, one group of community college
students was shown a color photograph of a 24-yearold
woman with a tattoo of a dragon on her arm. A
second group of students was shown the same photograph
but with the tattoo removed. Each participant
was asked to rate the participant on several characteristics,
including attractiveness, using a 5-point scale
(5 = most positive). Data similar to the attractiveness
ratings obtained in the study are shown in Table 2.1.
TABLE 2.1
Attractiveness ratings of a woman shown in a color photograph
for two samples of college students. For the first group
of students the woman in the photograph had a visible tattoo.
The students in the second group saw the same photograph
with the tattoo removed.
Visible Tattoo
No Visible Tattoo
1 2 4 3 2 4 4 3
2 2 1 3 5 4 2 4
2 5 4 3 4 5 3 3
You probably find it difficult to see any clear pattern
simply by looking at the list of numbers. Can you tell
whether the ratings for one group are generally higher
than those for the other group? One solution to this problem
is to organize each group of scores into a frequency
distribution, which provides a clearer view of the entire
group.
For example, the same attractiveness ratings that
are shown in Table 2.1 have been organized in a frequency
distribution graph in Figure 2.1. In the figure,
each individual is represented by a block that is placed
above that individual’s score. The resulting pile of
blocks shows a picture of how the individual scores are
distributed. For this example, it is now easy to see that
the attractiveness scores for the woman without a tattoo
are generally higher than the scores for the woman
with a tattoo; on average, the rated attractiveness of
the woman was around 2 with a tattoo and around 4
without a tattoo.
In this chapter we present techniques for organizing
data into tables and graphs so that an entire set of
scores can be presented in a relatively simple display or
illustration.
Photograph with
visible tattoo
1 2 4 4 5 6
Attractiveness rating
FIGURE 2.1
Attractiveness ratings for a
woman shown in a color photograph
with a visible tattoo
(upper graph) and with the
tattoo removed (lower graph).
Each box represents the score
for one individual.
1 2 4 4 5
Attractiveness rating
Photograph with
no visible tattoo
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