@cache_readonly
def _dispersion_factor(self):
    p = self.model.model_main.parameterization
    alpha = self.params[self.model.k_inflate:][(- 1)]
    mu = np.exp(self.predict(which='linear'))
    w = (1 - (self.predict() / mu))
    return (((1 + (alpha * (mu ** p))) ** 2) + (w * mu))
@cache_readonly
def _dispersion_factor(self):
    p = self.model.model_main.parameterization
    alpha = self.params[self.model.k_inflate:][(- 1)]
    mu = np.exp(self.predict(which='linear'))
    w = (1 - (self.predict() / mu))
    return (((1 + (alpha * (mu ** p))) ** 2) + (w * mu))