Sampling

Prepared By :-

Akshay Sikarwar

GLA University

Mathura

Sample

sample is a subset of some of the units in

the population

Example :-- Suppose we want to conduct a

research in GLA University which consist 5000

students and 1000 students included as

targeted population and only 500 students

are selected as sample for actual study.

What is Sampling ???

Sampling is the process of selecting

units (e.g., people, organizations)

from a population of interest so that

by studying the sample we may

fairly generalize our results back to

the population from which they

were chosen.

Why Sampling ????

Sampling is done because you usually cannot gather

data from the entire population.

Some other benefits are :-

Reduced cost: It is obviously less costly to obtain

data for a selected subset of a population, rather

than the entire population.

Speed: Observations are easier to collect and

summarize with a sample than with a complete

count. This consideration may be vital if the speed

of the analysis is important, such as through exit

polls in elections.

Greater scope: A complete census (enumeration) is

not practical or possible. Thus, surveys that rely on

sampling have greater flexibility regarding the type

of information that can be obtained.

Types of Sampling Techniques

There are two types of Sampling Techniques :-

1. Probability Sampling

2. Non-Probability Sampling

Note:- Probability and Non-Probability

Sampling are also known as Random and

Non-Random sampling respectively.

Probability Sampling

A probability sampling method is

any method of sampling that utilizes

some form of random selection.

Each individual in the population of

interest has an equal likelihood of

selection.

Non-Probability Sampling

In contrast with probability

sampling, non-probability sample is not

a product of a randomized selection

processes. Subjects in a non-probability

sample are usually selected on the

basis of their accessibility or by the

purposive personal judgment of the researcher.