statsmodels.discrete.discrete_model.Poisson.loglike

Poisson.loglike(params)[source]

Loglikelihood of Poisson model

Parameters:
params : array_like

The parameters of the model.

Returns:

loglike – The log-likelihood function of the model evaluated at params. See notes.

Return type:

float

Notes

\[\ln L=\sum_{i=1}^{n}\left[-\lambda_{i}+y_{i}x_{i}^{\prime}\beta-\ln y_{i}!\right]\]