Representative sample
Topic: Economic Data: Census, NSS, Surveys and Statistical Tools · NCERT: Class 11, Ch 2 "Collection of Data"
Meaning
A representative sample is a sample whose make-up matches the population's make-up. It is like a small copy of the whole. Because it mirrors the population, its results are fairly accurate for everyone. It also costs less and takes less time than counting every unit. A sample that leaves out some groups, or has too many of others, gives misleading results.
Example
A study covers agricultural labourers in Churachandpur district, Manipur. A 10% sample should include labourers from different villages, castes and landholding groups in about the same shares as the full district.
Don't confuse with
- Sample: this is any part of the population. A sample becomes representative only when its composition matches the population. People who refuse to answer, or a stale list of units, can stop a sample from being representative.
Related concepts
- Census
- Sample survey
- Population
- Sample
- Population parameter
- Random sampling
- Non-random sampling
- Sampling frame
- Lottery method
- Random number table