NegativeBinomial.deriv2()

statsmodels.genmod.families.links.NegativeBinomial.deriv2

NegativeBinomial.deriv2(p) [source]

Second derivative of the negative binomial link function.

Parameters:	p : array-like Mean parameters
Returns:	g’‘(p) : array The second derivative of the negative binomial transform link function

Notes

g’‘(x) = -(1+2*alpha*x)/(x+alpha*x^2)^2