In this lecture we will explain population and sample along with important characteristics of sample.

## What is Population?

The set of all measurements in which the investigator is interested is known as **population**. It is also known as Universe.

## What is Sample?

It is the subset of the population. Generally, we do random sampling.

When every possible element of a population have equal chances of getting selected then that is known as random sampling.

**EXAMPLE**

College have 1300 students. These 1300 students can be termed as population. If 30 students are to be selected in order to know the average age of the entire 1300 students, then these 30 students will constitute a sample.