BUILTIN MATHEMATICA SYMBOL
VarianceEquivalenceTest
 VarianceEquivalenceTest performs a hypothesis test on the with null hypothesis that the true population variances are equal , and alternative hypothesis that at least one is different.
 By default a probability value or value is returned.
 A small value suggests that it is unlikely that .
 The must be univariate .
 VarianceEquivalenceTest[{data_{1}, ...}] will choose the most powerful test that applies to the data.
 VarianceEquivalenceTest[{data_{1}, ...}, All] will choose all tests that apply to the data.
 VarianceEquivalenceTest[{data_{1}, ...}, "test"] reports the value according to .
 Most tests require normally distributed . If a test is less sensitive to a normality assumption, it is called robust. Some tests assume that is symmetric around its medians.
 The following tests can be used:

 "Bartlett"  normality  modified likelihood ratio test 
 "BrownForsythe"  robust  robust Levene test 
 "Conover"  symmetry  Conover's squared ranks test 
 "FisherRatio"  normality  based on 
 "Levene"  robust,symmetry  compares individual and group variances 
 VarianceEquivalenceTest[{data_{1}, ...}, "HypothesisTestData"] returns a HypothesisTestData object htd that can be used to extract additional test results and properties using the form htd["property"].
 VarianceEquivalenceTest[{data_{1}, ...}, "property"] can be used to directly give the value of .
 Properties related to the reporting of test results include:

 "AllTests"  list of all applicable tests 
 "AutomaticTest"  test chosen if Automatic is used 
 "DegreesOfFreedom"  the degrees of freedom used in a test 
 "PValue"  list of values 
 "PValueTable"  formatted table of values 
 "ShortTestConclusion"  a short description of the conclusion of a test 
 "TestConclusion"  a description of the conclusion of a test 
 "TestData"  list of pairs of test statistics and values 
 "TestDataTable"  formatted table of values and test statistics 
 "TestStatistic"  list of test statistics 
 "TestStatisticTable"  formatted table of test statistics 
 The following options can be given:

 For tests of variance, a cutoff is chosen such that is rejected only if . The value of used for the and properties is controlled by the SignificanceLevel option. This value is also used in diagnostic tests of assumptions including tests for normality and symmetry. By default is set to .
 Named settings for VerifyTestAssumptions in VarianceEquivalenceTest include:

 "Normality"  verify that all data is normally distributed 
 "Symmetry"  verify that all data is symmetric 
Test variances from two datasets for equivalence:
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Create a HypothesisTestData object for further property extraction:
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The full test table:
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Compare the variances of multiple datasets simultaneously:
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The variances of the datasets:
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