energy_test_statistic#
- energy_test_statistic(x, y, *, exponent=1, average=None, estimation_stat=EstimationStatistic.V_STATISTIC)[source]#
Homogeneity statistic.
Computes the statistic for homogeneity based on the energy distance, for random vectors corresponding to \(x\) and \(y\).
- Parameters
x (Array) – First random vector. The columns correspond with the individual random variables while the rows are individual instances of the random vector.
y (Array) – Second random vector. The columns correspond with the individual random variables while the rows are individual instances of the random vector.
exponent (float) – Exponent of the Euclidean distance, in the range \((0, 2)\).
average (Optional[Callable[[Array], Array]]) – A function that will be used to calculate an average of distances. This defaults to np.mean.
estimation_stat (Union[EstimationStatistic, Literal['U', 'V', 'u_statistic', 'v_statistic']]) – If EstimationStatistic.U_STATISTIC, calculate energy distance using Hoeffding’s unbiased U-statistics. Otherwise, use von Mises’s biased V-statistics. If this is provided as a string, it will first be converted to an EstimationStatistic enum instance.
- Returns
Value of the statistic for homogeneity based on the energy distance.
- Return type
Array
See also
energy_distance
Examples
>>> import numpy as np >>> import dcor >>> a = np.array([[1, 2, 3, 4], ... [5, 6, 7, 8], ... [9, 10, 11, 12], ... [13, 14, 15, 16]]) >>> b = np.array([[1, 0, 0, 1], ... [0, 1, 1, 1], ... [1, 1, 1, 1]]) >>> dcor.homogeneity.energy_test_statistic(a, a) 0.0 >>> dcor.homogeneity.energy_test_statistic(a, b) 35.2766732... >>> dcor.homogeneity.energy_test_statistic(b, b) 0.0