Sampling Design

Sampling design

a) Steps in Sampling Design:

Sampling design is a plan for obtaining a sample from a given population. It refers to the technique the researched would adopt in selecting items for the sample.

While developing a sampling design the researcher must pay attention to the points below which are known as steps of sampling design.

* Type of universe:

This step is to clearly define the set of objects, technically called the Universe, to be studied. The universe can be finite or infinite.

* Sampling unit:

A sampling unit has to be decided before selecting the sample. Sampling unit can be any units that researcher has to select for the study. Examples of sampling units, geographical area, construction unit, social unit etc.

* Source list:

This is a list of all items of a universe (in case of finite universe). It is also known as ‘sampling frame’ from which sample is to be drawn. The list should be comprehensive, correct, reliable and appropriate. It is extremely important for the source list to be as representative of the population as possible.

* Size of sample:

This refers to the number of items to be selected as sample from the universe. The size of the sample should be optimum. An optimum sample is one which fulfills the requirements of efficiency, representativeness, reliability and flexibility. The size of population variance also needs to be considered, i.e. for larger population bigger sample is needed.

* Parameters of interest:

In identifying the sample, one must consider the specific population parameters which are of interest.

* Budgetary Control:

Cost should also be considered during sampling design from the feasibility point of view. Not only size of the sample also the type of the sample has to be considered.

* Sampling procedure:

The researcher needs to choose a proper sample design procedure for the study. One must consider the design which for a given sample size and for a given cost, has a...