@stdlib/stats
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Standard library statistical functions.
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{{alias}}( [r, p] )
Returns a negative binomial distribution object.
Parameters
----------
r: number (optional)
Number of successes until experiment is stopped. Must be a positive
number. Default: `1`.
p: number (optional)
Success probability. Must be a number between `0` and `1`. Default:
`0.5`.
Returns
-------
nbinomial: Object
Distribution instance.
nbinomial.r: number
Number of trials. If set, the value must be a positive number.
nbinomial.p: number
Success probability. If set, the value must be a number between `0` and
`1`.
nbinomial.kurtosis: number
Read-only property which returns the excess kurtosis.
nbinomial.mean: number
Read-only property which returns the expected value.
nbinomial.mode: number
Read-only property which returns the mode.
nbinomial.skewness: number
Read-only property which returns the skewness.
nbinomial.stdev: number
Read-only property which returns the standard deviation.
nbinomial.variance: number
Read-only property which returns the variance.
nbinomial.cdf: Function
Evaluates the cumulative distribution function (CDF).
nbinomial.logpmf: Function
Evaluates the natural logarithm of the probability mass function (PMF).
nbinomial.mgf: Function
Evaluates the moment-generating function (MGF).
nbinomial.pmf: Function
Evaluates the probability mass function (PMF).
nbinomial.quantile: Function
Evaluates the quantile function at probability `p`.
Examples
--------
> var nbinomial = {{alias}}( 8.0, 0.5 );
> nbinomial.r
8.0
> nbinomial.p
0.5
> nbinomial.kurtosis
0.8125
> nbinomial.mean
8.0
> nbinomial.mode
7.0
> nbinomial.skewness
0.75
> nbinomial.stdev
4.0
> nbinomial.variance
16.0
> nbinomial.cdf( 2.9 )
~0.055
> nbinomial.logpmf( 3.0 )
~-2.837
> nbinomial.mgf( 0.2 )
~36.675
> nbinomial.pmf( 3.0 )
~0.059
> nbinomial.quantile( 0.8 )
11.0
See Also
--------