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Kuiper test for gamma distribution

Description

Performs Kuiper goodness-of-fit test for the hypothesis that the sample comes from a gamma distribution. The statistic combines the largest positive and negative empirical distribution deviations.

Hypothesis of Gamma Distribution The null hypothesis is that the data comes from a gamma distribution with positive shape parameter alpha and positive rate parameter beta.

Usage

from pysatl_criterion.statistics.goodness_of_fit import (
    KuiperGammaGofStatistic,
)


test_statistic = KuiperGammaGofStatistic(alpha=2, beta=1)
statistic_result = test_statistic.execute_statistic([0.42, 0.77, 1.05, 1.48, 1.96, 2.34, 3.12])
print(statistic_result)

Arguments

alpha - positive shape parameter of the gamma distribution. Default value is 1.0.

beta - positive rate parameter of the gamma distribution. Default value is 1.0.

rvs - array-like sample data passed to execute_statistic.

Details

The implementation computes

\[ V = D^+ + D^- \]

where \(D^+\) and \(D^-\) are one-sided deviations between empirical plotting positions and gamma CDF values.

Author(s)

Sergey Golovachev, Alexey Mironov

References

Kuiper, N.H. (1960): Tests concerning random points on a circle. - Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen, Series A, vol. 63, pp. 38-47.

Examples

from pysatl_criterion.statistics.goodness_of_fit import (
    KuiperGammaGofStatistic,
)


test_statistic = KuiperGammaGofStatistic(alpha=2, beta=1)
statistic_result = test_statistic.execute_statistic([0.42, 0.77, 1.05, 1.48, 1.96, 2.34, 3.12])
print(statistic_result)