The main difference between population and sample is that a population includes the entire group being studied, while a sample is a smaller part selected from that group. Researchers study populations to understand a group as a whole and use samples to collect data from a manageable number of people or items.
What Is Population?
In research, a population is the complete group of people, objects, or cases that a researcher wants to study. The population depends on the research topic and objectives.
For example, if a researcher wants to study the study habits of all university students in a country, the target population may include every university student in that country. In another study, the population might include teachers in one school, nurses in a hospital, or households in a particular city.
Population does not always mean people. It can also include schools, books, organizations, events, or other units of analysis.
What Is a Sample?
A sample is a smaller group selected from a population for research. Researchers collect information from this group to understand the larger population.
For example, a researcher may select 300 university students from several universities to study their study habits. These 300 students form the sample, while all university students included in the study’s target group form the population.
Researchers use different sampling methods, such as random sampling, stratified sampling, and convenience sampling. A suitable sample can save time, reduce costs, and make data collection easier. However, the sample should be selected carefully to reduce bias and improve how well the findings represent the population.
Difference Between Population and Sample
The difference between population and sample becomes clearer when we compare their meaning, size, purpose, and use in research.
| Basis | Population | Sample |
|---|---|---|
| Meaning | The entire group under study | A selected part of the population |
| Size | Usually larger | Usually smaller |
| Purpose | Defines the complete group of interest | Provides data for studying the population |
| Data collection | May require extensive time and resources | Often faster and less costly |
| Statistical measure | A measure is called a parameter | A measure is called a statistic |
| Example | All students at a university | 200 selected students from that university |
Examples of Population and Sample
Suppose a sociologist wants to study job satisfaction among nurses in a city. If the study covers all nurses working in that city, those nurses form the population. If the researcher selects 150 nurses to complete a questionnaire, the 150 nurses form the sample.
Similarly, if a researcher studies the reading habits of students in a college, all students in that college may form the population. The 100 students selected for interviews would be the sample.
These examples show that the population identifies the complete group of interest, while the sample identifies the group from which researchers actually collect data.
Frequently Asked Questions
1. What is the main difference between population and sample?
Population means the entire group being studied, while a sample is a smaller group selected from that population.
2. Why do researchers use samples?
Researchers use samples to save time, reduce costs, and collect data more efficiently when studying the entire population is difficult.
3. Can a sample be equal to the population?
Yes. If researchers collect data from every member of the population, the study becomes a census rather than a sample survey.
4. What is an example of population and sample in sociology?
All households in a town may form the population, while 250 selected households may form the sample for a study of family income.
5. What is the difference between a parameter and a statistic?
A parameter describes a characteristic of a population, while a statistic describes a characteristic calculated from a sample.
Conclusion
Understanding the difference between population and sample is essential for designing research and interpreting findings correctly. A clear population definition and an appropriate sampling method help researchers collect useful data and draw more reliable conclusions. Societypedia is an educational platform that provides simple explanations of Sociology, Psychology, Gender Studies, Research Methods, Anthropology, Education, and other social science concepts.