What is 'Statistical Significance'
Statistical significance is a result that is not likely to occur randomly, but rather is likely to be attributable to a specific cause. Statistical significance can be strong or weak, and is important to research in many math and sciencerelated fields, including medicine, sociology, psychology and biology. Statistical significance does not always indicate practical significance. In addition, it can be misinterpreted when researchers do not use language carefully in reporting their results.
BREAKING DOWN 'Statistical Significance'
The calculation of statistical significance (significance testing) is subject to a certain degree of error. The researcher must define in advance the probability of a sampling error (which exists in any test that does not include the entire population). Sample size is an important component of statistical significance in that larger samples are less prone to flukes. Only random, representative samples should be used in significance testing.
The level at which one can accept whether an event is statistically significant is known as the significance level or pvalue.

Statistically Significant
The likelihood that a result or relationship is caused by something ... 
Sample
A subset containing the characteristics of a larger population. ... 
Simple Random Sample
A subset of a statistical population in which each member of ... 
Standard Error
The standard deviation of the sampling distribution of a statistic. ... 
Sampling Error
A statistical error to which an analyst exposes a model simply ... 
Sampling
A process used in statistical analysis in which a predetermined ...

Fundamental Analysis
Explaining Standard Error
Standard error is a statistical term that measures the accuracy with which a sample represents a population. 
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. 
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. 
Economics
Understanding Statistics
Statistics provide the means to analyze data and then summarize it into a numerical form. 
Fundamental Analysis
What is a Representative Sample?
In statistics, a representative sample accurately represents the makeup of various subgroups in an entire data pool. 
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. 
Professionals
Interpreting Statistical Results
CFA Level 1  Test Statistics and Interpreting Results 
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 ... 
Professionals
Statistical Concepts And Market Returns
CFA Level 1  Statistical Concepts And Market Returns  Basics

What's the difference between a representative sample and a random sample?
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How do researchers ensure that a simple random sample is an accurate representation ...
Learn which methods researchers employ to ensure that a simple random sample best approximates the larger population being ... Read Answer >> 
What are the advantages of using a simple random sample to study a larger population?
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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 >> 
When is it better to use systematic over simple random sampling?
Learn when systematic sampling is better than simple random sampling, such as in the absence of data patterns and when there ... Read Answer >> 
What's the difference between a representative sample and a convenience sample?
Learn the difference between convenience sampling and representative sampling and the advantages and disadvantages of each ... Read Answer >>