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Chapter 1: Introduction and Graphical Displays
variables
and
quantitative variables
.
Qualitative variables
are variables
whose values are nonnumeric and can be placed into distinct categories
according to some characteristic or attribute.
Quantitative variables
are
variables whose values are numeric and as such, these values can be
measured or counted. Further, quantitative variables can be further
subdivided into two groups. These two quantitative variable groups are
discrete variables
and
continuous variables
. When data is collected on
any variable, we call this collection of values a
data set
where each value in
the data set is called a
data value
.
Figure 1-2
shows these relationships.
Figure1-2:
Breakdown of the types of variables
Following are the formal definitions for quantitative, qualitative, discrete
and continuous variables.
Definition: Quantitative Variables
Quantitative variables are variables whose values are numeric in nature.