default double maxChiSquared(final int degreesOfFreedom) {
		final var gd = new GammaDistribution(degreesOfFreedom/2.0, 2.0);
		return gd.icdf().apply(1 - pValue());
/*
		return ChiSquaredDistribution.of(degreesOfFreedom)
			.inverseCumulativeProbability(1 - pValue());

 */
	}
Return the maximal allowed chi-squared value for the given degrees of
freedom.

@param degreesOfFreedom the degree of freedom
@return the maximal allowed chi-squared value
jenetics.incubator/src/main/java/io/jenetics/incubator/stat/ChiSquared.java