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TwoSampleTTestPowerAnalysisGetSampleSize Method (Double, Double, Double, Double, Double, Double, TwoSampleHypothesis)

Estimates the number of samples necessary to attain the required power level for the given effect size.

Namespace:  Accord.Statistics.Testing.Power
Assembly:  Accord.Statistics (in Accord.Statistics.dll) Version: 3.8.0
public static TwoSampleTTestPowerAnalysis GetSampleSize(
	double delta,
	double variance1,
	double variance2,
	double proportion = 1,
	double power = 0.8,
	double alpha = 0.05,
	TwoSampleHypothesis hypothesis = TwoSampleHypothesis.ValuesAreDifferent
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Type: SystemDouble
The minimum detectable difference.
Type: SystemDouble
The first sample variance.
Type: SystemDouble
The second sample variance.
proportion (Optional)
Type: SystemDouble
The proportion of observations in the second group when compared to the first group. A proportion of 2:1 results in twice more samples in the second group than in the first. Default is 1.
power (Optional)
Type: SystemDouble
The desired power level. Default is 0.8.
alpha (Optional)
Type: SystemDouble
The desired significance level. Default is 0.05.
hypothesis (Optional)
Type: Accord.Statistics.TestingTwoSampleHypothesis
The alternative hypothesis (research hypothesis) to be tested.

Return Value

Type: TwoSampleTTestPowerAnalysis
The required number of samples.
See Also