Concept of Population and Sample / Research methodology

*Population:*

A population refers to the entire group of individuals, items, or data points that you want to understand or describe. It includes every element of interest, typically defined by specific characteristics, such as:

- Geographic location
- Age range
- Occupation
- Ethnicity

Examples:

- All students in a country
- All employees in a company
- All residents in a city

*Sample:*

A sample is a subset of individuals, items, or data points selected from the population to represent it. Sampling helps estimate population characteristics without collecting data from every individual.

Types of sampling:

1. *Probability sampling*:
- Random sampling
- Stratified sampling
- Systematic sampling
2. *Non-probability sampling*:
- Convenience sampling
- Purposive sampling
- Quota sampling

Key differences:

*Population* *Sample*

- Entire group Subset of population
- Every element Representative selection
- Difficult/costly to collect data More feasible and efficient
- Provides exact information Estimates population characteristics

*Why sampling?*

1. Cost-effectiveness
2. Time efficiency
3. Increased accuracy (reduced errors)
4. Easier data analysis
5. Better representation (avoiding bias)

*Sampling techniques:*

1. Simple Random Sampling (SRS)
2. Cluster Sampling
3. Stratified Sampling
4. Systematic Sampling
5. Multi-stage Sampling

*Common sampling errors:*

1. Sampling bias
2. Non-response error
3. Measurement error
4. Sampling frame error

Understanding populations and samples is crucial in research, statistics, and data analysis to ensure reliable and accurate conclusions.

Do you have specific questions about populations or samples?

1. CONCEPT OF POPULATION
AND SAMPLE
BY- SUJIT KUMAR BHOI

2. WHAT IS POPULATION ?
In research, a population is the
entire group of people, objects,
events, or organizations that are of
interest to the researcher. The
population is defined based on the
research objectives and the specific
parameters or attributes under
investigation.

3. WHAT IS SAMPLE?
sample is a subset of individuals from a
larger population. Sampling means selecting
the group that you will actually collect data
from in your research. For example, if you
are researching the opinions of students in
your university, you could survey a sample
of 100 students..

6. PROBHABILITY SAMPLING
Each member of the population has
an equal chance of being selected
for the sample. This method is
often used in public opinion
studies and election polling.
Probability sampling methods
include simple random sampling,
stratified sampling, systematic
sampling, and cluster sampling.

7. NON PROBABILITY
SAMPLING
Nonprobability sampling is a method
of selecting a sample group from a
population that doesn't use random
sampling techniques. It's a quick,
inexpensive way to gather data, but
it can lead to biased results

8. CONTINUE
Convenience sampling, where participants are
selected based on their availability and
convenience

Quota sampling

Purposeful sampling, which includes
heterogeneity sampling, homogeneous
sampling, deviant sampling, and expert
sampling

9. CONCLUSION
The sample must be representative of the
population. A representative sample is a
subset of the population that reflects the
characteristics of the population. A
sample is biased if it systematically favors
a certain outcome. Random selection
eliminates bias.

10. THANK YOU
VERY MUCH!