Background
A stratified sample is a technique in statistics used to ensure that distinct subgroups within a population are represented proportionally in the sample. This method is particularly useful when the population is heterogeneous, meaning there is significant variability within its subgroups.
Historical Context
The stratified sampling method has been utilized in statistical research for decades, with its development stemming from the need to produce more accurate and representative samples. By dividing populations into strata based on specific characteristics, researchers can gain more detailed and reliable insights into the behavior and traits of the overall population.
Definitions and Concepts
A stratified sample is obtained by dividing a population into different subgroups or “strata” that share similar characteristics. After forming these subgroups, a sample is drawn from each in a manner proportional to their size or presence in the entire population. This approach ensures that all relevant subgroups are adequately represented.
- Population: The entire pool from which a sample is drawn.
- Subgroup/Strata: Subcategories of the population that share one or more common characteristics.
- Proportional Representation: Ensuring each subgroup’s presence in the sample is proportional to its presence in the population.
Major Analytical Frameworks
Classical Economics
Classical economists did not focus on statistical methods for sampling, but stratified sampling would align with the classical emphasis on understanding different economic classes and their roles in production and consumption.
Neoclassical Economics
Neoclassical theory, which emphasizes marginal analysis, can benefit from stratified sampling by ensuring that different consumer preferences within varied subgroups are accurately represented.
Keynesian Economics
Stratified sampling can help Keynesian economists by providing accurate data on how various population subgroups are affected by macroeconomic variables such as changes in government policy and economic stimuli.
Marxian Economics
Marxian economics would benefit from stratified sampling by examining how different classes or strata within society are affected by economic and production relations.
Institutional Economics
The stratified sample technique aligns with the institutional perspective, which focuses on the role of institutions and diverse groups within the economy.
Behavioral Economics
Behavioral economists can use stratified samples to study deviations from rational behavior and how they are influenced by group-specific factors.
Post-Keynesian Economics
Post-Keynesians, who emphasize the variability in economic behavior and uncertainty, can use stratified sampling to study these phenomena across different economic actors and groups.
Austrian Economics
Stratified sampling could assist Austrian economists in examining market processes and entrepreneurship across different segments of the population.
Development Economics
In development economics, stratified sampling can be instrumental in accurately assessing the impacts of development policies across diverse economic demographics.
Monetarism
Monetarist studies can use stratified sampling to gather data on how different segments of the population respond to changes in monetary policy.
Comparative Analysis
Stratified sampling differs from random sampling in that it ensures representation of all subgroups, while random sampling may not. Quota sampling shares similarities with the stratified stretch, but it involves non-random techniques to achieve proportionality.
Case Studies
Examples of stratified sampling in research include demographic studies on consumer behavior across different income levels, health surveys that account for varying risk factors among groups, and electoral studies ensuring representation of various political affiliations.
Suggested Books for Further Studies
- “Sampling Techniques” by William G. Cochran
- “Survey Methodology” by Robert M. Groves, Floyd J. Fowler, and Mick P. Couper
- “Statistics for People Who (Think They) Hate Statistics” by Neil J. Salkind
Related Terms with Definitions
- Quota Sample: A non-random sampling technique where participants are selected to ensure the sample represents certain characteristics of the population.
- Random Sample: A sampling method where each member of the population has an equal chance of being selected, ensuring randomness and reducing sampling bias.
