proportional sample
Học thuậtThân thiện
Definition
Noun: A proportional sample is a type of sample obtained by dividing the entire population into distinct subgroups (called strata) and then taking a random sample from each subgroup. The size of the sample taken from each stratum is proportional to the size of that stratum within the total population.
Usage
This term is used in the context of statistics and research methodology. It describes a specific sampling technique designed to ensure that the sample accurately reflects the composition of the entire population with respect to the chosen strata.
Examples
- The researcher used a proportional sample to ensure the survey accurately represented the age distribution of the city's residents.
- To study voting patterns, they drew a proportional sample from each of the state's electoral districts.
- The accuracy of the poll was improved by employing a proportional sample stratified by income level.
Advanced Usage
- Stratified Random Sampling: A proportional sample is the result of a specific application of stratified random sampling where the sampling fraction is the same for every stratum. This is contrasted with a , where the sampling fractions differ between strata.
- Ensuring Representativeness: The primary goal of a proportional sample is to create a miniature, proportional model of the population, thereby reducing sampling bias for the stratification variables.
Variants and Related Words
- Stratified Sample (n): A more general term for any sample taken from stratified subgroups. A proportional sample is a specific type of stratified sample.
- Stratification (n): The process of dividing a population into subgroups (strata).
- Stratum (n): (Plural: ) One of the homogeneous subgroups into which a population is divided.
Synonyms
- Stratified Proportional Sample
- Proportionate Stratified Sample
Related Terms (Not Phrasal Verbs)
- Random Sample (n): A sample where every member of the population has an equal chance of being selected. A proportional sample involves taking random samples each stratum.
- Sampling Frame (n): The list or source from which a sample, including a proportional sample, is drawn.
- Quota Sample (n): A non-probability sampling method that also aims for proportional representation but does not use random selection within quotas, unlike a proportional sample.
Noun
- the population is divided into strata and a random sample is taken from each stratum