def test_value_error_for_negative_counts(self):
with pytest.raises(ValueError):
population_attributable_fraction(-5, 1, 1, 1)
def test_compare_to_formula(self):
paf_formula = ((25 + 10) / 100 - 10 / 50) / ((25 + 10) / 100)
paf = population_attributable_fraction(25, 25, 10, 40)
npt.assert_allclose(paf, paf_formula)
def test_paf_is_zero(self):
paf = population_attributable_fraction(25, 25, 25, 25)
assert paf == 0