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Nominal scale

The nominal scale is the simplest form of measurement. It
is simply a system of assigning numerical symbols to events to
label them. It is the grouping of objects or people without any
specific quantitative relationship between the categories. Nominal
scales are adopted for the labelling of non-quantitative variables
(containing no numerical implications) that are unique and
different from each other. Nominal scales classify members of ◆ Description
a population into 2 or more categories. The categories must be
mutually exclusive and exhaustive, that is, each and every one of
the members of the population must be capable of being classified
in one and only one category. Nominal scales have no arithmetical
properties. No category is greater or less than any other category.

Category values are simply names (hence the term nominal). The
only mathematical statements that can be made about nominal data
consist of relative comparisons between the numbers of members
of the population in each category, called proportions.
In nutshell nominal scale has the following properties:

◆ The system of empirical relations consists only of different
classes. There is no notion of ordering between the classes.

◆ Any other numbering or symbolic representation of classes
is an acceptable measure, but there is no notion of magnitude
associated with numbers or symbols.
◆ It simply labels the objects. Numbers only serve as labels or
tags to identify and classify objects (not up, down, better, or
worse). ◆ No order, distance,
and origin
◆ When used for identification, there is a strict one-to-one
match between numbers and objects.

◆ Figures do not reflect the amount of property an object has.

◆ Counting is the only possible operation on numbers on a
nominal scale.

◆ Only a limited number of statistical analysis based on
frequency numbers are allowed.

Example: In which diet do you belong to? The possible answers
are:

◆ Vegetarian.

◆ Non-vegetarian.

In nominal scale we may label Vegetarian as ‘1’, and Non-
vegetarian as ‘2’. It does not in any way mean any of the diet
plans is better than the other. They are just used as an identity for

SGOU - SLM - MCom Research Methodology 101