def test_moments(self):
poisson_m1, poisson_m2 = poisson.moment(1, 12), poisson.moment(2, 12)
zip_m0 = sm.distributions.zipoisson.moment(0, 12, 0)
zip_m1 = sm.distributions.zipoisson.moment(1, 12, 0)
zip_m2 = sm.distributions.zipoisson.moment(2, 12, 0)
assert_allclose(1, zip_m0, rtol=1e-10)
assert_allclose(poisson_m1, zip_m1, rtol=1e-10)
assert_allclose(poisson_m2, zip_m2, rtol=1e-10)
def _moment(self, n, mu, w):
return (1 - w) * poisson.moment(n, mu)
