Maneesh Jha
Scales of measurement
Understanding the scales of measurement
B.opt 3rd year

Contents
1: Properties of measurement
2: Scales of measurement

Properties of measurement
Scales of measurement is how a variable is defined
?
What is that variable
A variable is a characteristic that can be measured and that can assume different
values. Height, age, income, province or country of birth, grades obtained at school
and type of housing are all examples of variables. Variables may be classified into
two main categories: categorical and numeric
https://www150.statcan.gc.ca/n1/edu/power-pouvoir/ch8/5214817-eng.htm

Who developed it ?
Stanely stevens
https://science.sciencemag.org/content/103/2684/677
Developed the four common scales of
measurement: nominal, ordinal, interval and ratio.
Each scale of measurement has properties that
determine how to properly analyse the data.

Properties evaluated are
Identify: refers to each value having unique meaning
Magnitude: means the values have an ordered relationship to
one another
Equal intervals: means that data points along scale are equal
so that the data point between one and two will be same as the
data point between five and six
A minimum value of zero : means a scale has true zero points

https://studyonline.unsw.edu.au/blog/types-of-

Nominal scale
Defines property data but does not have numerical meaning,
data can be placed in to categories
Examples of nominal data include eye colour and country of birth
Sub-categories:
1:-Nominal with order: cold , warm ,hot ,very hot
2:-Nominal without order: male and female …
3:-Dichotomous: have only two level or category e.g yes and No
https://lsc.cornell.edu/wp-content/uploads/2016/01/Intro-to-measurement-and-statistics.pdf

Ordinal scale of measurement
Defines data that is placed in specific order ,These values can’t
be added to or subtracted from.
An example of this kind of data would include satisfaction data
points in a survey, where ‘one = happy, two = neutral, and three =
unhappy
https://lsc.cornell.edu/wp-content/uploads/2016/01/Intro-to-measurement-and-statistics.pdf

Interval scale of measurement
contains properties of nominal and ordered data, but the
difference between data points can be quantified. This type of
data shows both the order of the variables and the exact
differences between the variables. They can be added to or
subtracted from each other, but not multiplied or divided
For example, 40 degrees is not 20 degrees multiplied by two.
This scale is also characterised by the fact that the number zero
is an existing variable. In the ordinal scale, zero means that the
data does not exist. In the interval scale, zero has meaning – for
example, if you measure degrees, zero has a temperature
https://lsc.cornell.edu/wp-content/uploads/2016/01/Intro-to-measurement-and-statistics.pdf

Ratio scale of measurement
Include properties from all four scales of measurement. The
data is nominal and defined by an identity, can be classified in
order, contains intervals and can be broken down into exact
value. Weight, height and distance are all examples of ratio
variables. Data in the ratio scale can be added, subtracted,
divided and multiplied.
Ratio scales also differ from interval scales in that the scale has a
‘true zero’.
The number zero means that the data has no value point. An
example of this is height or weight, as someone cannot be zero
centimetres tall or weigh zero kilos – or be negative centimetres or
negative kilos.
https://lsc.cornell.edu/wp-content/uploads/2016/01/Intro-to-measurement-and-statistics.pdf

Thank you