statsmodels.genmod.families.links.NegativeBinomial.deriv¶ NegativeBinomial.deriv(p)[source]¶ Derivative of the negative binomial transform Parameters:¶ p : array_like¶Mean parameters Returns:¶ g’(p) – The derivative of the negative binomial transform link function Return type:¶ ndarray Notes g’(x) = 1/(x+alpha*x^2)