statsmodels.genmod.families.links.NegativeBinomial.inverse_deriv¶ NegativeBinomial.inverse_deriv(z)[source]¶ Derivative of the inverse of the negative binomial transform Parameters:¶ zarray_likeUsually the linear predictor for a GLM or GEE model Returns:¶ g^(-1)’(z)ndarrayThe value of the derivative of the inverse of the negative binomial link