This presentation shows the difference between nominal and ordinal scale of measurement

1. Nominal and Ordinal scales
of measurement
Dr. Roma Smart Joseph
Teacher Educator, Lucknow,
UP, India
romasmart@ymail.com

3.  Scales of measurement refer to ways in which
variables/numbers are defined and categorized.
 Each scale of measurement has certain properties which in turn
determines the appropriateness for use of certain statistical
analyses.

4. • The scales of measurement or
‘levels of measure‘ are the result of
the work of Stanley Steven Smith.
• He proposed in 1946 that all
measurements were performed with
the help of four scales namely:
1.Nominal scale.
2.Ordinal scale.
3.Interval scale.
4.Ratio scale.

7. Points of difference Nominal scales Ordinal scales
Meaning Nominal data are those items which
are distinguished by a simple
naming system. They are data with
no numeric value.
Ordinal data is data which is placed
into some kind of order by their
position on the scale.
Category The subjects are only allocated to
different categories hence, it is also
called categorical data.
Ordinal data and variables are
considered as “in between”
categorical and quantitative
variables.
Quantitative
Value
Nominal scales do not denote the
quantitative level or value.
Ordinal scales assign numbers to
the data but do not serve the
purpose of calculations.

8. Points of difference Nominal scales Ordinal scales
Numerical
significance
Nominal scales are mutually
exclusive and do not overlap and
none of them have any numerical
significance.
Ordinal scales are typically
measures of non-numeric
concepts like satisfaction,
happiness, discomfort etc.
Examples • Gender
• Religion
• Marital status, etc.
• The first, second and third
person in a competition.
• Economic status:
lower,middle,upper class etc.

10. • Data need not be inherently numeric to be useful in an
analysis.
• The level of detail used in a system of classification
should be appropriate, based on the reasons for making
the classification and the uses to which the information
will be put.