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statsmodels.discrete.discrete_model.Poisson.cdf

Poisson.cdf(X) [source]

Poisson model cumulative distribution function

Parameters: X (array-like) – X is the linear predictor of the model. See notes.
Returns:
Return type: The value of the Poisson CDF at each point.

Notes

The CDF is defined as

\[\exp\left(-\lambda\right)\sum_{i=0}^{y}\frac{\lambda^{i}}{i!}\]

where \(\lambda\) assumes the loglinear model. I.e.,

\[\ln\lambda_{i}=X\beta\]

The parameter X is \(X\beta\) in the above formula.

© 2009–2012 Statsmodels Developers
© 2006–2008 Scipy Developers
© 2006 Jonathan E. Taylor
Licensed under the 3-clause BSD License.
http://www.statsmodels.org/stable/generated/statsmodels.discrete.discrete_model.Poisson.cdf.html