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Unit 2 Sample Size

Unit Sample Size

2

Learning Outcomes

The following outcomes are expected from the learner after going through the unit:

◆ learn about the concept of sample size and various factors influencing it.
◆ know the concept of optimum sample size.

◆ understand various methods for calculating sample size.
◆ gain insights on sampling errors and biases.

Background

Most of the researches are based on sample data as it is economical and operationally
feasible. The research result to be valid and accurate, it is essential that the sample is
representative of the population characteristics. For instance, a study is conducted to find
out how many people in a state want to pursue Ph.D. as part of their higher education.
It is not practical to ask every single person, so you pick a smaller group (called a
sample), such as post graduate students from various colleges, to represent the whole
state. But how will you decide the number of individuals to be included in that sample?
That’s where sample size comes in. Understanding sample size considerations and
potential errors associated with sampling is vital for conducting valid and trustworthy
research. By addressing these issues adequately, research findings better reflect the target
population and enhance the overall quality of research outcomes. Hence in research,
sampling should be done in more organised and scientific way. This unit aims to provide
an insight on the determination of an optimum sample size.

Keywords

Sample size, Optimum sample size, Sampling error, Non-sampling error, Sampling
bias

68 SGOU - SLM -MCom Research Methodology