atoti.experimental.stats.chi2 module

Chi-square distribution.

For more information read:

• scipy.stats.chi2

• The Chi-square Wikipedia page

atoti.experimental.stats.chi2.cdf(point, *, degrees_of_freedom)

Cumulative distribution function for a chi-square distribution.

The cdf of the chi-square distribution with k degrees of freedom is

\[\operatorname {cdf}(x)=\dfrac {\gamma (\frac {k}{2},\,\frac {x}{2})}{\Gamma (\frac {k}{2})}\]

where \(\Gamma\) is the gamma function and \(\gamma\) the lower incomplete gamma function.

Parameters

• point (Measure) – The point where the function is evaluated.

• degrees_of_freedom (Union[int, float, Measure, MeasureConvertible]) – The number of degrees of freedom. Must be positive.

See also

The Chi-square Wikipedia page

Return type

Measure

atoti.experimental.stats.chi2.pdf(point, *, degrees_of_freedom)

Probability density function for a chi-square distribution.

The pdf of the chi-square distribution with k degrees of freedom is

\[\operatorname {pdf}(x)=\dfrac {x^{\frac {k}{2}-1}e^{-\frac {x}{2}}} {2^\frac {k}{2}\Gamma \left(\frac {k}{2}\right)}\]

where \(\Gamma\) is the gamma function.

Parameters

• point (Measure) – The point where the function is evaluated.

• degrees_of_freedom (Union[int, float, Measure, MeasureConvertible]) – The number of degrees of freedom. Must be positive.

See also

The Chi-square Wikipedia page

Return type

Measure

atoti.experimental.stats.chi2.ppf(point, *, degrees_of_freedom)

Percent point function for a chi-square distribution.

Also called inverse cumulative distribution function.

Parameters

• point (Measure) – The point where the function is evaluated.

• degrees_of_freedom (Union[int, float, Measure, MeasureConvertible]) – The number of degrees of freedom. Must be positive.

See also

The Chi-square Wikipedia page

Return type

Measure