Sample Design in Research

 

 Definition:

Sample design is the framework or plan used to select a subset (sample) of a population for observation and analysis. It determines how many, whom, and how to select participants that will represent the larger population in a research study.

Effective sample design ensures that the data collected is valid, reliable, and generalizable.

 Components of a Sample Design

Component

Description

Target Population

The total group the researcher wants to study (e.g., all mutual fund investors in India)

Sampling Frame

A list or database from which the sample will be drawn (e.g., AMFI investor list)

Sampling Unit

The basic unit selected for sampling (e.g., individual investor, household)

Sample Size

The number of units selected from the population (e.g., 400 respondents)

Sampling Method

The technique used to select sample units (probability or non-probability)

Data Collection Method

How data is collected from the sample (survey, interview, observation)

 Types of Sampling Methods

 1. Probability Sampling

Each member of the population has a known, non-zero chance of being selected.

Method

Description

Example

Simple Random Sampling

Every unit has an equal chance of selection

Lottery method to select 100 investors

Systematic Sampling

Selecting every kth item from a list

Every 5th account holder in a customer database

Stratified Sampling

Population divided into strata; samples taken from each

Sampling investors by age group or region

Cluster Sampling

Population divided into clusters; random clusters selected

Sampling entire bank branches or cities

 2. Non-Probability Sampling

Some units have unknown or zero chance of being selected. Easier and cost-effective, but may introduce bias.

Method

Description

Example

Convenience Sampling

Selection based on availability or ease

Surveying people in a finance workshop

Judgmental Sampling

Researcher selects based on judgment or expertise

Choosing senior investors for in-depth interviews

Quota Sampling

Fixed quotas for certain groups (like stratified, but non-random)

50% male and 50% female investors

Snowball Sampling

Existing subjects recruit future subjects

Finding angel investors through referrals

 Example of Sample Design in Finance Research

Title:
“A Study on Financial Literacy and Investment Behavior among Salaried Employees in Delhi”

Component

Example

Population

All salaried employees in Delhi

Sampling Frame

Employee records from companies and institutions

Sampling Unit

Individual salaried employee

Sample Size

300 respondents

Sampling Method

Stratified random sampling based on income groups

Data Collection

Structured questionnaire survey

 Factors to Consider in Sample Design

1.      Objectives of the Study

2.      Type of Population (homogeneous/heterogeneous)

3.      Time and Cost Constraints

4.      Degree of Accuracy Required

5.      Availability of Sampling Frame

 Summary Table

Term

Explanation

Sample

A subset of the population

Sampling Frame

The list from which the sample is drawn

Sampling Method

Procedure used to select the sample

Sample Size

Number of elements in the sample

Representative Sample

Accurately reflects the population

 

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