public function dataProviderForCDF() { return [[1, 0, 1, 0.75], [0, 1, 1, 0.25], [1, 1, 1, 0.5], [2, 3, 4, 0.4220208696226307], [4, 3, 2, 0.6475836176504333], [5, 5, 5, 0.5]]; }