Ejemplo n.º 1
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def test_oob_sarimax():
    xreg = rs.rand(wineind.shape[0], 2)
    fit = ARIMA(order=(1, 1, 1),
                seasonal_order=(0, 1, 1, 12),
                out_of_sample_size=15).fit(y=wineind, exogenous=xreg)

    fit_no_oob = ARIMA(order=(1, 1, 1),
                       seasonal_order=(0, 1, 1, 12),
                       out_of_sample_size=0,
                       suppress_warnings=True).fit(y=wineind[:-15],
                                                   exogenous=xreg[:-15, :])

    # now assert some of the same things here that we did in the former test
    oob = fit.oob()

    # compare scores:
    scoring = get_callable(fit_no_oob.scoring, VALID_SCORING)
    no_oob_preds = fit_no_oob.predict(n_periods=15, exogenous=xreg[-15:, :])
    assert np.allclose(oob, scoring(wineind[-15:], no_oob_preds), rtol=1e-2)

    # show params are still the same
    assert np.allclose(fit.params(), fit_no_oob.params(), rtol=1e-2)

    # show we can add the new samples and get the exact same forecasts
    xreg_test = rs.rand(5, 2)
    fit_no_oob.add_new_observations(wineind[-15:], xreg[-15:, :])
    assert np.allclose(fit.predict(5, xreg_test),
                       fit_no_oob.predict(5, xreg_test),
                       rtol=1e-2)

    # Show we can get a confidence interval out here
    preds, conf = fit.predict(5, xreg_test, return_conf_int=True)
    assert all(isinstance(a, np.ndarray) for a in (preds, conf))
Ejemplo n.º 2
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def test_add_new_obs_deprecated():
    endog = wineind
    train, test = endog[:125], endog[125:]
    model = ARIMA(order=(1, 0, 0))

    model.fit(train)

    with pytest.warns(DeprecationWarning):
        model.add_new_observations(test)
Ejemplo n.º 3
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def test_add_new_obs_deprecated():
    endog = wineind
    train, test = endog[:125], endog[125:]
    model = ARIMA(order=(1, 0, 0))

    model.fit(train)

    with warnings.catch_warnings(record=True) as w:
        warnings.simplefilter("always")
        model.add_new_observations(test)
        assert len(w)
        # Might be more than one warning, so quick pass
        assert any(issubclass(wrn.category, DeprecationWarning) and
                   'pmdarima' in str(wrn.message) for wrn in w)
Ejemplo n.º 4
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def test_oob_for_issue_28():
    # Continuation of above: can we do one with an exogenous array, too?
    xreg = rs.rand(hr.shape[0], 4)
    arima = ARIMA(order=(2, 1, 2),
                  suppress_warnings=True,
                  out_of_sample_size=10).fit(y=hr, exogenous=xreg)

    oob = arima.oob()
    assert not np.isnan(oob)

    # Assert that the endog shapes match. First is equal to the original,
    # and the second is the differenced array, with original shape - d.
    assert np.allclose(arima.arima_res_.data.endog, hr, rtol=1e-2)
    assert arima.arima_res_.model.endog.shape[0] == hr.shape[0] - 1

    # Now assert the same for exog
    assert np.allclose(arima.arima_res_.data.exog, xreg, rtol=1e-2)
    assert arima.arima_res_.model.exog.shape[0] == xreg.shape[0] - 1

    # Compare the OOB score to an equivalent fit on data - 10 obs, but
    # without any OOB scoring, and we'll show that the OOB scoring in the
    # first IS in fact only applied to the first (train - n_out_of_bag)
    # samples
    arima_no_oob = ARIMA(order=(2, 1, 2),
                         suppress_warnings=True,
                         out_of_sample_size=0).fit(y=hr[:-10],
                                                   exogenous=xreg[:-10, :])

    scoring = get_callable(arima_no_oob.scoring, VALID_SCORING)
    preds = arima_no_oob.predict(n_periods=10, exogenous=xreg[-10:, :])
    assert np.allclose(oob, scoring(hr[-10:], preds), rtol=1e-2)

    # Show that the model parameters are exactly the same
    xreg_test = rs.rand(5, 4)
    assert np.allclose(arima.params(), arima_no_oob.params(), rtol=1e-2)

    # Now assert on the forecast differences.
    with_oob_forecasts = arima.predict(n_periods=5, exogenous=xreg_test)
    no_oob_forecasts = arima_no_oob.predict(n_periods=5, exogenous=xreg_test)

    assert_raises(AssertionError, assert_array_almost_equal,
                  with_oob_forecasts, no_oob_forecasts)

    # But after we update the no_oob model with the latest data, we should
    # be producing the same exact forecasts

    # First, show we'll fail if we try to add observations with no exogenous
    assert_raises(ValueError, arima_no_oob.add_new_observations, hr[-10:],
                  None)

    # Also show we'll fail if we try to add mis-matched shapes of data
    assert_raises(ValueError, arima_no_oob.add_new_observations, hr[-10:],
                  xreg_test)

    # Show we fail if we try to add observations with a different dim exog
    assert_raises(ValueError, arima_no_oob.add_new_observations, hr[-10:],
                  xreg_test[:, :2])

    # Actually add them now, and compare the forecasts (should be the same)
    arima_no_oob.add_new_observations(hr[-10:], xreg[-10:, :])
    assert np.allclose(with_oob_forecasts,
                       arima_no_oob.predict(n_periods=5, exogenous=xreg_test),
                       rtol=1e-2)