What is 'Stratified Random Sampling'
Stratified random sampling is a method of sampling that involves the division of a population into smaller groups known as strata. In stratified random sampling, the strata are formed based on members' shared attributes or characteristics. A random sample from each stratum is taken in a number proportional to the stratum's size when compared to the population. These subsets of the strata are then pooled to form a random sample.
BREAKING DOWN 'Stratified Random Sampling'
The main advantage with stratified sampling is how it captures key population characteristics in the sample. Similar to a weighted average, this method of sampling produces characteristics in the sample that are proportional to the overall population. Stratified sampling works well for populations with a variety of attributes, but is otherwise ineffective, as subgroups cannot be formed.

Simple Random Sample
A subset of a statistical population in which each member of ... 
Sampling
A process used in statistical analysis in which a predetermined ... 
Systematic Sampling
A type of probability sampling method in which sample members ... 
Sample
A subset containing the characteristics of a larger population. ... 
Sampling Error
A statistical error to which an analyst exposes a model simply ... 
Sampling Distribution
A probability distribution of a statistic obtained through a ...

Investing
How to Use Stratified Random Sampling
Stratified random sampling is a technique best used with a sample population easily broken into distinct subgroups. Samples are then taken from each subgroup based on the ratio of the subgroupâ€™s ... 
Fundamental Analysis
Understanding the Simple Random Sample
A simple random sample is a subset of a statistical population in which each member of the subset has an equal probability of being chosen. 
Fundamental Analysis
What is a Representative Sample?
In statistics, a representative sample accurately represents the makeup of various subgroups in an entire data pool. 
Fundamental Analysis
How Does Sampling Work?
Sampling is a term used in statistics that describes methods of selecting a predefined representative number of data from a larger data population. 
Professionals
Sampling and Estimation
CFA Level 1  Sampling and Estimation sampling error, in depth information on confidence intervals and tdistributions 
Economics
What is Systematic Sampling?
Systematic sampling is similar to random sampling, but it uses a pattern for the selection of the sample. 
Fundamental Analysis
Explaining Standard Error
Standard error is a statistical term that measures the accuracy with which a sample represents a population. 
Fundamental Analysis
Explaining the Central Limit Theorem
Central limit theorem is a fundamental concept in probability theory. 
Professionals
Calculating Confidence Intervals
CFA Level 1  Confidence Intervals  Calculations 
Professionals
Interpreting Statistical Results
CFA Level 1  Test Statistics and Interpreting Results

What is the difference between a simple random sample and a stratified random sample?
Learn about the differences between simple random sampling and stratified random sampling, and learn about the advantages ... Read Answer >> 
What are some examples of stratified random sampling?
Learn what simple random sampling and stratified random sampling are, some examples of stratified random samples, and how ... Read Answer >> 
How does stratified random sampling influence government policy decisions?
Understand how governments use stratified random sampling to collect more precise data to help in making better informed ... Read Answer >> 
What are the best selection methods for creating a simple random sample?
Discover some of the methods that researchers and pollsters utilize to select a simple random sample from a population group ... Read Answer >> 
What are some common financial sampling methods?
Read about the differences between various common financial sampling methods for financial analysts, statisticians, marketers ... Read Answer >> 
What are the advantages and disadvantages of stratified random sampling?
Understand the process for stratified random sampling and its advantages and disadvantages for selecting a sample to approximate ... Read Answer >>