Brian S. Everitt A Handbook of Statistical Analyses using SPSS

Chapter 4
Multiple Linear
Regression:
Temperatures in America
and Cleaning Cars
4.1 Description of Data
In this chapter, we shall deal with two sets of data where interest lies in
either examining how one variable relates to a number of others or in
predicting one variable from others. The first data set is shown in Table
4.1 and includes four variables, sex, age, extroversion, and car, the latter
being the average number of minutes per week a person spends looking
after his or her car. According to a particular theory, people who score
higher on a measure of extroversion are expected to spend more time
looking after their cars since a person may project their self-image through
themselves or through objects of their own. At the same time, car-cleaning
behavior might be related to demographic variables such as age and sex.
Therefore, one question here is how the variables sex, age, and extroversion
affect the time that a person spends cleaning his or her car.
The second data set, reported by Peixoto (1990) is given in Table 4.2,
and shows the normal average January minimum temperature (in F) along
with the longitude and latitude for 56 cities in the U.S. (Average minimum
temperature for January is found by adding together the daily minimum
© 2004 by Chapman & Hall/CRC Press LLC