BartlettTest Class

public sealed class BartlettTest : MultiSampleTest<double>

Public NotInheritable Class BartlettTest
	Inherits MultiSampleTest(Of Double)

public ref class BartlettTest sealed : public MultiSampleTest<double>

[<SealedAttribute>]
type BartlettTest =  
    class
        inherit MultiSampleTest<float>
    end

The BartlettTest type exposes the following members.

	Name	Description
	BartlettTest	Constructs a new BartlettTest..
	BartlettTest(IDataFrame)	Constructs a new BartlettTest for the specified vector.
	BartlettTest(VectorDouble)	Constructs a new BartlettTest for the specified vector array.
	BartlettTest(VectorDouble, IGrouping)	Constructs a new BartlettTest for the specified vector.

	Name	Description
	DegreesOfFreedom	Gets the degrees of freedom for this chi-square distribution.
	Distribution	Gets the probability distribution used in the hypothesis test. (Inherited from HypothesisTest.)
	Grouping	Gets the grouping that divides Sample into groups. (Inherited from MultiSampleTestT.)
	HypothesisType	Gets or sets whether the test is one or two-tailed. (Inherited from HypothesisTest.)
	Name	Gets the name of the hypothesis test. (Overrides HypothesisTestName.)
	PValue	Gets the probability that the test statistic would take on the calculated value under the alternate hypothesis. (Inherited from HypothesisTest.)
	Sample	Gets the vector that contains the sample data. (Inherited from MultiSampleTestT.)
	Samples	Gets the collection of samples for the test. (Inherited from MultiSampleTestT.)
	SignificanceLevel	Gets the significance level used to test the null hypothesis. (Inherited from HypothesisTest.)
	Statistic	Gets the value of the test statistic. (Inherited from HypothesisTest.)

	Name	Description
	Equals	Determines whether the specified object is equal to the current object. (Inherited from Object.)
	GetConfidenceInterval	Returns the confidence interval for the test parameter for the default confidence level. (Inherited from HypothesisTest.)
	GetConfidenceInterval(Double)	Returns the confidence interval for the test parameter for the specified confidence level. (Inherited from HypothesisTest.)
	GetHashCode	Serves as the default hash function. (Inherited from Object.)
	GetLowerCriticalValue	Gets the lower critical value for the hypothesis test's current significance level. (Inherited from HypothesisTest.)
	GetLowerCriticalValue(Double)	Gets the lower critical value for the hypothesis test at the specified significance level. (Inherited from HypothesisTest.)
	GetPValue	Gets the probability that the test statistic would take on the calculated value under the specified alternate hypothesis. (Inherited from HypothesisTest.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	GetUpperCriticalValue	Gets the upper critical value for the test statistic at the hypothesis test's current significance level. (Inherited from HypothesisTest.)
	GetUpperCriticalValue(Double)	Gets the upper critical value for the test statistic at the specified significance level. (Inherited from HypothesisTest.)
	Reject	Returns whether the null hypothesis is rejected using the default significance level. (Inherited from HypothesisTest.)
	Reject(Double)	Returns whether the null hypothesis is rejected using the specified significance level. (Inherited from HypothesisTest.)
	Summarize	Returns a string containing a human-readable summary of the object. (Inherited from HypothesisTest.)
	Summarize(SummaryOptions)	Returns a string containing a human-readable summary of the object using the specified options. (Inherited from HypothesisTest.)
	ToString	Returns a string that represents the current object. (Inherited from HypothesisTest.)

Use the BartlettTest class to test the hypothesis that a number of samples have the same variance. This property is called homogeneity of variance.

Some statistical procedures, such as the Analysis of Variance, assume that variances are the same across groups.

Bartlett's test is a relatively fast test for homogeneity of variances. The test is based on the assumption that the samples are normally distributed. It is sensitive to violations of this assumption. In practical terms, this means that Bartlett's test cannot adequately distinguish between violation of homogeneity of variances and violation of the normality assumption. In such a case, Levene's test gives more meaningful results.

Reference