Factor analysis is different from many of the other techniques presented in this book.
It is not designed to test hypotheses or to tell you whether one group is significantly
different from another. It is included in SPSS as a ‘data reduction’ technique. It takes
a large set of variables and looks for a way the data may be ‘reduced’ or summarized
using a smaller set of factors or components. It does this by looking for ‘clumps’ or
groups among the inter correlations of a set of variables. This is an almost impossible
task to do ‘by eye’ with anything more than a small number of variables.
There are two main approaches to factor analysis that you will see described in the
literature—exploratory and confirmatory. Exploratory factor analysis is often used in
the early stages of research to gather information about (explore) the interrelationships
among a set of variables. Confirmatory factor analysis, on the other hand, is a
more complex and sophisticated set of techniques used later in the research process
to test (confirm) specific hypotheses or theories concerning the structure underlying
a set of variables.