statsmodels.discrete.truncated_model.TruncatedLFPoisson.hessian¶ TruncatedLFPoisson.hessian(params)¶ Generic Truncated model Hessian matrix of the loglikelihood Parameters:¶ paramsarray_likeThe parameters of the model Returns:¶ hessndarray, (k_vars, k_vars)The Hessian, second derivative of loglikelihood function, evaluated at params