Types of Data

Data can be classified on Nominal, Ordinal, Interval and Ratio scale.

Nominal Data are simple classifications. Such data cannot be subjected to mathematical operations like addition, subtraction, multiplication and division.

Ordinal Data are simple classifications that can be ranked. Such data cannot be subjected to mathematical operations but can be ranked.

Interval Data are simple classifications that can be ranked and can be subjected to mathematical operations of addition and subtraction. Interval data don’t have absolute zero.

Ratio Data are Data that can be subjected to all mathematical operations and have absolute zero.

Example: Suppose a questionnaire comprises of following questions.

Q1. What is your name? Response here is a Nominal Data

Q2. How old are you? Response is Ratio Data

Q3. What is your date of birth? Response here is Nominal Data

Q4. How to you rate our services? Response here is Ordinal Data

Not good (1)   average (2)   good (3)    very good (4)

Q5. What is your body temperature? Response is interval data