statsmodels.genmod.families.links.CDFLink.inverse_deriv2¶
- CDFLink.inverse_deriv2(z)[source]¶
Second derivative of the inverse link function g^(-1)(z).
- Parameters:
z (array_like) – z is usually the linear predictor for a GLM or GEE model.
- Returns:
g^(-1)’’(z) – The value of the second derivative of the inverse of the link function
- Return type:
ndarray
Notes
This method should be overwritten by subclasses.
The inherited method is implemented through numerical differentiation.