Page 60 - SREENARAYANAGURU OPEN UNIVERSITY

taken to analyse the population.

The technique of choosing or adopting a representative part
of the population for the purpose of data collection to facilitate
◆ Representative research is known as sampling. The representative part is known
as a sample and each element in the sample is known as the sample
unit. The sample selection process or technique is called sampling
and the survey conducted on the basis of sample is described as
sample survey.
Characteristics of a good sample
The quality of the sample decides whether the outcome of the
research is reliable or not. Hence, while choosing the sample one
must keep the following points in mind.

◆ Should ensure that the sample is true representative of the
population.

◆ Should be unbiased in order to be accurate.

◆ Should be capable of giving a precise estimate free from
errors.

◆ Should be of adequate size in order to yield reliable results.

Advantages

◆ Sampling helps in saving time

◆ Sampling helps in saving cost

◆ It helps to give reliable result

◆ It is necessary when population is infinite

◆ It is necessary when study of an item causes its destructions

Disadvantages

◆ Sample surveys should be carefully planned and executed.
Otherwise, the result obtained may be inaccurate.

◆ It requires the service of experts. In their absence, information
from samples may not be relied upon.

◆ If information is required for each and every unit, it cannot
be applied.
◆ The chances of errors and bias affects the reliability of results.

54 SGOU - SLM -MCom Research Methodology