DEFINITION of 'Statistical Significance'
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.
INVESTOPEDIA EXPLAINS '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.

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