statsmodels.genmod.families.links.NegativeBinomial.deriv2¶
- NegativeBinomial.deriv2(p)[source]¶
Second derivative of the negative binomial link function.
- Parameters:
- parray_like
Mean parameters
- Returns:
- g’’(p)
ndarray
The second derivative of the negative binomial transform link function
- g’’(p)
Notes
g’’(x) = -(1+2*alpha*x)/(x+alpha*x^2)^2