This document discusses different scales of measurement used in research and statistics: nominal, ordinal, interval, and ratio scales. Nominal scales simply assign numbers to label variables, like player numbers. Ordinal scales rank variables but intervals may not be equal, like education levels. Interval scales have equal intervals, like temperatures. Ratio scales have a true zero point, like weights. The document provides examples of variables that use each scale and references a textbook on research methodology.

1. Business
Research
Methods
Scaling

2. Hello!
Prepared by
Rajakrishnan M
Assistant Professor in Commerce CA
Dr. N.G.P. Arts and Science College
Coimbatore
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3. Scaling
Let’s start…
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4. “
”
Scales of measurement in
research and statistics are the
different ways in which variables
are defined and grouped into
different categories.
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5. “
”
Sometimes called the level of measurement, it
describes the nature of the values assigned to the
variables in a data set.
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6. Classification of
measurement scales
 Nominal scale
 Ordinal scale
 Interval scale
 Ratio scale
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7. Nominal scale is
simply a system of
assigning number
symbols to events in
order to label them.
Nominal scale
The usual example of
this is the assignment
of numbers of
basketball players in
order to identify
them.
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Nominal scale
Examples of nominal variables include:
genotype, blood type, zip code, gender,
race, eye color, political party

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Nominal scale

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Ordinal scale
The lowest level of the ordered scale that is
commonly used is the ordinal scale.
The ordinal scale places events in order, but there
is no attempt to make the intervals of the scale
equal in terms of some rule.

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Ordinal scale
The use of an ordinal scale implies a statement of
‘greater than’ or ‘less than’ (an equality statement
is also acceptable) without our being able to state
how much greater or less.
The real difference between ranks 1 and 2 may be
more or less than the difference between ranks 5
and 6.

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Ordinal scale

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Ordinal scale
Examples of ordinal variables include:
Socio economic status (“low income”,”middle
income”,”high income”), education level (“high
school”,”BS”,”MS”,”PhD”), income level (“less
than 50K”, “50K-100K”, “over 100K”),
satisfaction rating (“extremely dislike”,
“dislike”, “neutral”, “like”, “extremely like”).

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Interval scale
In the case of interval scale, the intervals are
adjusted in terms of some rule that has been
established as a basis for making the units equal.
The units are equal only in so far as one accepts
the assumptions on which the rule is based.

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Interval scale
Interval scales provide more powerful
measurement than ordinal scales for interval
scale also incorporates the concept of equality of
interval.
As such more powerful statistical measures can
be used with interval scales.

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Interval scale
Examples of interval variables include:
temperature (Farenheit), temperature
(Celcius), pH, SAT score (200-800), credit
score (300-850).

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Ratio scale
Ratio scales have an absolute or true zero of
measurement. The term ‘absolute zero’ is not
as precise as it was once believed to be.
We can conceive of an absolute zero of length
and similarly we can conceive of an absolute
zero of time.

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Ratio scale
For example, the zero point on a centimeter
scale indicates the complete absence of length
or height.
But an absolute zero of temperature is
theoretically unobtainable and it remains a
concept existing only in the scientist’s mind.

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Ratio scale
Examples of ratio variables include:
Enzyme activity, dose amount, reaction rate,
flow rate, concentration, pulse, weight, length,
temperature in Kelvin (0.0 Kelvin really does
mean “no heat”), survival time.

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Source: QuestionPro

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Source: QuestionPro

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Measurement scales

23. Reference
 Research Methodology by C.R.Kothari

24. Thanks!
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