Scales of Measurement

Scales of measurement is a classification that describes the nature of information within the values assigned to variables. 

It is an important characteristic of data. It determines what types of descriptive, graphical and inferential statistical analysis can be used. 

Psychologist S.S. Stevens developed the best-known classification with four levels or scales of measurement, i.e., nominal, ordinal, interval and ratio

Although this framework originated in psychology, it is widely criticized by scholars in other disciplines. 

These four scales or levels at which researchers measure and collect their data may found to reflect a unique hierarchy in their level of functioning. The lowest lead is nominal and the highest is ratio. 

These four levels can be defined in detail as following - 

Nominal Scales

(Data in the form of naming or categories)

Ordinal Scales 

(Data in order of rank) 

Interval Scales 

(Equal interval have no absolute zero) 

Ratio Scales 

(Equal intervals having absolute zero point)