test_comparisons.py 文件源码

def test_aic_data_dependence():
    d = norm.rvs(size=1000)
    p = norm.logpdf(d)
    c = ChainConsumer()
    c.add_chain(d, posterior=p, num_free_params=1, num_eff_data_points=1000)
    c.add_chain(d, posterior=p, num_free_params=1, num_eff_data_points=500)
    aics = c.comparison.aic()
    assert len(aics) == 2
    assert aics[0] == 0
    expected = (2.0 * 1 * 2 / (500 - 1 - 1)) - (2.0 * 1 * 2 / (1000 - 1 - 1))
    assert np.isclose(aics[1], expected, atol=1e-3)