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Statistical Distributions

PDFChiSquared​

Returns the density of a chi-squared value:
Syntax:     PDFChiSquared(x, df)

Example:   PDFChiSquared(2, 5) → 0.138
            PDFChiSquared(7.8, 3) → 0.023

InvChiSquared​

Returns the chi-squared value for a given probability:
Syntax:     InvChiSquared(p, df)

Example:   InvChiSquared(0.95, 3) → 7.81
            InvChiSquared(0.99, 1) → 6.63

CDFExponential​

Returns the cumulative probability for an exponential distribution:
Syntax:     CDFExponential(x, rate)

Example:   CDFExponential(10, 0.5) → 0.9933
            CDFExponential(5, 1) → 0.9933

PDFExponential​

Returns the probability density for the exponential distribution:
Syntax:     PDFExponential(x, rate)

Example:   PDFExponential(1, 0.5) → 0.303
            PDFExponential(2, 1) → 0.135

InvExponential​

Returns the x-value for a given probability:
Syntax:     InvExponential(p, rate)

Example:   InvExponential(0.5, 1) → 0.6931
            InvExponential(0.8, 0.5) → 3.2189

CDFPoisson​

Returns the cumulative probability of the Poisson distribution:
Syntax:     CDFPoisson(x, lambda)

Example:   CDFPoisson(5, 3) → 0.916
            CDFPoisson(10, 7) → 0.901

PMFPoisson​

Returns the exact probability for a count in the Poisson distribution:
Syntax:     PMFPoisson(x, lambda)

Example:   PMFPoisson(4, 2) → 0.09
            PMFPoisson(0, 5) → 0.0067