214 The Marketing Book
Table 9.7 Regression, automatic interaction detection and discriminant
analysis – a comparison
Method Based on Marketing
applicationsMain advantages Main limitationsRegression
analysisDeveloping a
function
expressing the
association (or
relationship)
between
dependent and
independent
variablesFor segmentation,
consumer
behaviour analysis,
sales forecasting
(Speed, 1994)Enables
predictions about
a dependent
variable (say, sales
figures). Provides
measures of
association
between
independent
variables and
certain important
marketing
dependent
variablesRequires fitting a
regression line and
determining the
parameters. This
could be quite
complex and lead
to certain errorsAutomatic
interaction
detectionA computer-based
sequential routine
attempting to
classify objects
into groups as
possible, by
minimizing the
within-group sum
of squaresFor market
segments analysis,
assess the effects
of advertising on
retail sales, predict
brand loyalty sales
prediction, etc.Suitable for
identifying the
different variables
affecting market
segments;
determining the
importance of
each independent
variable and the
form in which it
affects the
dependent variableLess powerful than
regression.
Minimum group
size should be no
less than 30, and
the original sample
size should be
quite largeDiscriminant
analysisMaximize the ratio
of variance
between group
means, not within-
group variancePredicting brand
loyalty, consumer
innovators, like/
dislike of a service
(or product), etc.Enables
predictions of
dependent
variablesIdentifying the
statistical
significance of the
discriminant
function; multiple
discriminant
analysis requires a
computer program