Unlock: Tweedie Distribution

The Tweedie distribution is the one-parameter subfamily of the exponential dispersion model (EDM) family characterized by a power variance function V(mu) = mu^p. Special cases recover the Normal (p=0), Poisson (p=1), Gamma (p=2), and Inverse Gaussian (p=3). The intermediate range 1<p<2 produces a compound Poisson-Gamma distribution with a point mass at zero and a continuous positive part, which is the canonical model for insurance loss severity. The page covers the EDM construction, the four special-case identifications, and the compound-Poisson-Gamma representation; the applied actuarial treatment lives on ActuaryPath.