NegativeBinomialLink

class superglm.NegativeBinomialLink(theta: float = 1.0)

Bases: object

Negative binomial link: eta = log(mu / (mu + theta)).

Canonical link for NB2(θ), parametrised so that mu > 0 maps to eta in (-inf, 0).

Parameters:

thetafloat

The NB overdispersion parameter (must be > 0).

deriv3_inverse(

eta: NDArray,

) → NDArray

d³μ/dη³ = θe(1 + 4e + e²)/(1-e)⁴. Wood (2011) Appendix D.