def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC
    from sklearn.base import is_classifier
    # KernelRidge is used for testing 1) regression analyses 2) n-dimensional
    # predictions.
    from sklearn.kernel_ridge import KernelRidge
    from sklearn.preprocessing import LabelEncoder
    from sklearn.metrics import roc_auc_score, mean_squared_error

    epochs = make_epochs()
    y_4classes = np.hstack((epochs.events[:7, 2], epochs.events[7:, 2] + 1))
    if check_version('sklearn', '0.18'):
        from sklearn.model_selection import (KFold, StratifiedKFold,
                                             ShuffleSplit, LeaveOneLabelOut)
        cv_shuffle = ShuffleSplit()
        cv = LeaveOneLabelOut()
        # XXX we cannot pass any other parameters than X and y to cv.split
        # so we have to build it before hand
        cv_lolo = [(train, test) for train, test in cv.split(
                   X=y_4classes, y=y_4classes, labels=y_4classes)]

        # With sklearn >= 0.17, `clf` can be identified as a regressor, and
        # the scoring metrics can therefore be automatically assigned.
        scorer_regress = None
    else:
        from sklearn.cross_validation import (KFold, StratifiedKFold,
                                              ShuffleSplit, LeaveOneLabelOut)
        cv_shuffle = ShuffleSplit(len(epochs))
        cv_lolo = LeaveOneLabelOut(y_4classes)

        # With sklearn < 0.17, `clf` cannot be identified as a regressor, and
        # therefore the scoring metrics cannot be automatically assigned.
        scorer_regress = mean_squared_error
    # Test default running
    gat = GeneralizationAcrossTime(picks='foo')
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    assert_raises(ValueError, gat.fit, epochs)
    with warnings.catch_warnings(record=True):
        # check classic fit + check manual picks
        gat.picks = [0]
        gat.fit(epochs)
        # check optional y as array
        gat.picks = None
        gat.fit(epochs, y=epochs.events[:, 2])
        # check optional y as list
        gat.fit(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(len(gat.picks_), len(gat.ch_names), 1)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
                 "prediction, no score>", '%s' % gat)
    assert_equal(gat.ch_names, epochs.ch_names)
    # test different predict function:
    gat = GeneralizationAcrossTime(predict_method='decision_function')
    gat.fit(epochs)
    # With classifier, the default cv is StratifiedKFold
    assert_true(gat.cv_.__class__ == StratifiedKFold)
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 15, 14, 1))
    gat.predict_method = 'predict_proba'
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 15, 14, 2))
    gat.predict_method = 'foo'
    assert_raises(NotImplementedError, gat.predict, epochs)
    gat.predict_method = 'predict'
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 15, 14, 1))
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predicted 14 epochs, no score>",
                 "%s" % gat)
    gat.score(epochs)
    assert_true(gat.scorer_.__name__ == 'accuracy_score')
    # check clf / predict_method combinations for which the scoring metrics
    # cannot be inferred.
    gat.scorer = None
    gat.predict_method = 'decision_function'
    assert_raises(ValueError, gat.score, epochs)
    # Check specifying y manually
    gat.predict_method = 'predict'
    gat.score(epochs, y=epochs.events[:, 2])
    gat.score(epochs, y=epochs.events[:, 2].tolist())
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predicted 14 epochs,\n scored "
                 "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.050 (s), length: 0.050 (s), n_time_windows: 15>",
                 "%s" % gat.train_times_)
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.050 (s), length: 0.050 (s), n_time_windows: 15 x 15>",
                 "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    gat_ = copy.deepcopy(gat)
    with use_log_level('error'):
        assert_raises(ValueError, gat_.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] ==
                gat.y_true_.shape[0] ==
                len(gat.y_pred_[0][0]) == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(len(gat.train_times_['slices']) == 15 ==
                np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(len(gat.test_times_['slices']) == 15 ==
                np.shape(gat.scores_)[0])
    assert_true(len(gat.test_times_['slices'][0]) == 15 ==
                np.shape(gat.scores_)[1])

    # Test score_mode
    gat.score_mode = 'foo'
    assert_raises(ValueError, gat.score, epochs)
    gat.score_mode = 'fold-wise'
    scores = gat.score(epochs)
    assert_array_equal(np.shape(scores), [15, 15, 5])
    gat.score_mode = 'mean-sample-wise'
    scores = gat.score(epochs)
    assert_array_equal(np.shape(scores), [15, 15])
    gat.score_mode = 'mean-fold-wise'
    scores = gat.score(epochs)
    assert_array_equal(np.shape(scores), [15, 15])
    gat.predict_mode = 'mean-prediction'
    with warnings.catch_warnings(record=True) as w:
        gat.score(epochs)
        assert_true(any("score_mode changed from " in str(ww.message)
                        for ww in w))

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    with warnings.catch_warnings(record=True):  # not vectorizing
        scores = gat.score(epochs)
    assert_true(isinstance(scores, np.ndarray))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check
    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.score(epochs)
    assert_true(len(gat.scores_) == len(gat.estimators_) == 8)  # training time
    assert_equal(len(gat.scores_[0]), 15)  # testing time

    # Test start stop training & test cv without n_fold params
    y_4classes = np.hstack((epochs.events[:7, 2], epochs.events[7:, 2] + 1))
    train_times = dict(start=0.090, stop=0.250)
    gat = GeneralizationAcrossTime(cv=cv_lolo, train_times=train_times)
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=y_4classes)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times_['times'][0], epochs.times[6])
    assert_equal(gat.train_times_['times'][-1], epochs.times[9])

    # Test score without passing epochs & Test diagonal decoding
    gat = GeneralizationAcrossTime(test_times='diagonal')
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.fit(epochs)
    assert_raises(RuntimeError, gat.score)
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.predict(epochs)
    scores = gat.score()
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))
    assert_array_equal([tim for ttime in gat.test_times_['times']
                        for tim in ttime], gat.train_times_['times'])
    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction', cv=2)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    with warnings.catch_warnings(record=True):
        # There are some empty test folds because of n_trials
        gat.predict(epochs[7:])
        gat.score(epochs[7:])

    # Test training time parameters
    gat_ = copy.deepcopy(gat)
    # --- start stop outside time range
    gat_.train_times = dict(start=-999.)
    with use_log_level('error'):
        assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(start=999.)
    assert_raises(ValueError, gat_.fit, epochs)
    # --- impossible slices
    gat_.train_times = dict(step=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=999.)
    assert_raises(ValueError, gat_.fit, epochs)

    # Test testing time parameters
    # --- outside time range
    gat.test_times = dict(start=-999.)
    with warnings.catch_warnings(record=True):  # no epochs in fold
        assert_raises(ValueError, gat.predict, epochs)
    gat.test_times = dict(start=999.)
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat.predict, epochs)
    # --- impossible slices
    gat.test_times = dict(step=.000001)
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat.predict, epochs)
    gat_ = copy.deepcopy(gat)
    gat_.train_times_['length'] = .000001
    gat_.test_times = dict(length=.000001)
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat_.predict, epochs)
    # --- test time region of interest
    gat.test_times = dict(step=.150)
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 5, 14, 1))
    # --- silly value
    gat.test_times = 'foo'
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat.predict, epochs)
    assert_raises(RuntimeError, gat.score)
    # --- unmatched length between training and testing time
    gat.test_times = dict(length=.150)
    assert_raises(ValueError, gat.predict, epochs)
    # --- irregular length training and testing times
    # 2 estimators, the first one is trained on two successive time samples
    # whereas the second one is trained on a single time sample.
    train_times = dict(slices=[[0, 1], [1]])
    # The first estimator is tested once, the second estimator is tested on
    # two successive time samples.
    test_times = dict(slices=[[[0, 1]], [[0], [1]]])
    gat = GeneralizationAcrossTime(train_times=train_times,
                                   test_times=test_times)
    gat.fit(epochs)
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.score(epochs)
    assert_array_equal(np.shape(gat.y_pred_[0]), [1, len(epochs), 1])
    assert_array_equal(np.shape(gat.y_pred_[1]), [2, len(epochs), 1])
    # check cannot Automatically infer testing times for adhoc training times
    gat.test_times = None
    assert_raises(ValueError, gat.predict, epochs)

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc, predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    with use_log_level('error'):
        assert_raises(ValueError, gat.score, epochs2)
        gat.score(epochs)
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime(cv=cv_shuffle)
    gat.fit(epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.predict(epochs)
    assert_raises(ValueError, gat.predict, epochs[:10])

    # Make CV with some empty train and test folds:
    # --- empty test fold(s) should warn when gat.predict()
    gat._cv_splits[0] = [gat._cv_splits[0][0], np.empty(0)]
    with warnings.catch_warnings(record=True) as w:
        gat.predict(epochs)
        assert_true(len(w) > 0)
        assert_true(any('do not have any test epochs' in str(ww.message)
                        for ww in w))
    # --- empty train fold(s) should raise when gat.fit()
    gat = GeneralizationAcrossTime(cv=[([0], [1]), ([], [0])])
    assert_raises(ValueError, gat.fit, epochs[:2])

    # Check that still works with classifier that output y_pred with
    # shape = (n_trials, 1) instead of (n_trials,)
    if check_version('sklearn', '0.17'):  # no is_regressor before v0.17
        gat = GeneralizationAcrossTime(clf=KernelRidge(), cv=2)
        epochs.crop(None, epochs.times[2])
        gat.fit(epochs)
        # With regression the default cv is KFold and not StratifiedKFold
        assert_true(gat.cv_.__class__ == KFold)
        gat.score(epochs)
        # with regression the default scoring metrics is mean squared error
        assert_true(gat.scorer_.__name__ == 'mean_squared_error')

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2, 4]  # 4 tested
    # nicely ordered labels or not
    le = LabelEncoder()
    y = le.fit_transform(epochs.events[:, 2])
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Univariate and multivariate prediction
    svc = SVC(C=1, kernel='linear', probability=True)
    reg = KernelRidge()

    def scorer_proba(y_true, y_pred):
        return roc_auc_score(y_true, y_pred[:, 0])

    # We re testing 3 scenario: default, classifier + predict_proba, regressor
    scorers = [None, scorer_proba, scorer_regress]
    predict_methods = [None, 'predict_proba', None]
    clfs = [svc, svc, reg]
    # Test all combinations
    for clf, predict_method, scorer in zip(clfs, predict_methods, scorers):
        for y in ys:
            for n_class in n_classes:
                for predict_mode in ['cross-validation', 'mean-prediction']:
                    # Cannot use AUC for n_class > 2
                    if (predict_method == 'predict_proba' and n_class != 2):
                        continue

                    y_ = y % n_class

                    with warnings.catch_warnings(record=True):
                        gat = GeneralizationAcrossTime(
                            cv=2, clf=clf, scorer=scorer,
                            predict_mode=predict_mode)
                        gat.fit(epochs, y=y_)
                        gat.score(epochs, y=y_)

                    # Check that scorer is correctly defined manually and
                    # automatically.
                    scorer_name = gat.scorer_.__name__
                    if scorer is None:
                        if is_classifier(clf):
                            assert_equal(scorer_name, 'accuracy_score')
                        else:
                            assert_equal(scorer_name, 'mean_squared_error')
                    else:
                        assert_equal(scorer_name, scorer.__name__)
Exemple #2
0
def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC
    from sklearn.preprocessing import LabelEncoder
    from sklearn.metrics import mean_squared_error

    raw = io.Raw(raw_fname, preload=False)
    events = read_events(event_name)
    picks = pick_types(raw.info, meg='mag', stim=False, ecg=False,
                       eog=False, exclude='bads')
    picks = picks[0:2]
    decim = 30

    # Test on time generalization within one condition
    with warnings.catch_warnings(record=True):
        epochs = Epochs(raw, events, event_id, tmin, tmax, picks=picks,
                        baseline=(None, 0), preload=True, decim=decim)
    # Test default running
    gat = GeneralizationAcrossTime()
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    assert_raises(ValueError, gat.fit, epochs, picks='foo')
    with warnings.catch_warnings(record=True):
        # check classic fit + check manual picks
        gat.fit(epochs, picks=[0])
        # check optional y as array
        gat.fit(epochs, y=epochs.events[:, 2])
        # check optional y as list
        gat.fit(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(len(gat.picks_), len(gat.ch_names), 1)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
                 "prediction, no score>", '%s' % gat)
    assert_equal(gat.ch_names, epochs.ch_names)
    gat.predict(epochs)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predicted 14 epochs, no score>",
                 "%s" % gat)
    gat.score(epochs)
    gat.score(epochs, y=epochs.events[:, 2])
    gat.score(epochs, y=epochs.events[:, 2].tolist())
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predicted 14 epochs,\n scored "
                 "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.047 (s), length: 0.047 (s), n_time_windows: 15>",
                 "%s" % gat.train_times)
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.047 (s), length: 0.047 (s), n_time_windows: 15 x 15>",
                 "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    gat_ = copy.deepcopy(gat)
    assert_raises(ValueError, gat_.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] ==
                gat.y_true_.shape[0] ==
                len(gat.y_pred_[0][0]) == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(len(gat.train_times['slices']) == 15 ==
                np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(len(gat.test_times_['slices']) == 15 ==
                np.shape(gat.scores_)[0])
    assert_true(len(gat.test_times_['slices'][0]) == 15 ==
                np.shape(gat.scores_)[1])

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    scores = gat.score(epochs)
    assert_true(isinstance(scores, list))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check

    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.score(epochs)
    assert_true(len(gat.scores_) == len(gat.estimators_) == 8)  # training time
    assert_equal(len(gat.scores_[0]), 15)  # testing time

    # Test start stop training
    gat = GeneralizationAcrossTime(train_times={'start': 0.090,
                                                'stop': 0.250})
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times['times_'][0], epochs.times[6])
    assert_equal(gat.train_times['times_'][-1], epochs.times[9])

    # Test score without passing epochs
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    assert_raises(RuntimeError, gat.score)
    gat.predict(epochs, test_times='diagonal')  # Test diagonal decoding
    scores = gat.score()
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))

    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    gat.predict(epochs[7:])
    assert_raises(ValueError, gat.predict, epochs, test_times='hahahaha')
    assert_raises(RuntimeError, gat.score)
    gat.score(epochs[7:])

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc, predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    assert_raises(ValueError, gat.score, epochs2)
    gat.score(epochs)
    scores = sum(scores, [])  # flatten
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    assert_raises(ValueError, gat.predict, epochs[:10])

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2, 4]  # 4 tested
    # nicely ordered labels or not
    le = LabelEncoder()
    y = le.fit_transform(epochs.events[:, 2])
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Univariate and multivariate prediction
    svc = SVC(C=1, kernel='linear')

    class SVC_proba(SVC):
        def predict(self, x):
            probas = super(SVC_proba, self).predict_proba(x)
            return probas[:, 0]

    svcp = SVC_proba(C=1, kernel='linear', probability=True)
    clfs = [svc, svcp]
    scorers = [None, mean_squared_error]
    # Test all combinations
    for clf, scorer in zip(clfs, scorers):
        for y in ys:
            for n_class in n_classes:
                y_ = y % n_class
                with warnings.catch_warnings(record=True):
                    gat = GeneralizationAcrossTime(cv=2, clf=clf)
                    gat.fit(epochs, y=y_)
                    gat.score(epochs, y=y_, scorer=scorer)
def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC
    from sklearn.base import is_classifier
    # KernelRidge is used for testing 1) regression analyses 2) n-dimensional
    # predictions.
    from sklearn.kernel_ridge import KernelRidge
    from sklearn.preprocessing import LabelEncoder
    from sklearn.metrics import roc_auc_score, mean_squared_error

    epochs = make_epochs()
    y_4classes = np.hstack((epochs.events[:7, 2], epochs.events[7:, 2] + 1))
    if check_version('sklearn', '0.18'):
        from sklearn.model_selection import (KFold, StratifiedKFold,
                                             ShuffleSplit, LeaveOneLabelOut)
        cv_shuffle = ShuffleSplit()
        cv = LeaveOneLabelOut()
        # XXX we cannot pass any other parameters than X and y to cv.split
        # so we have to build it before hand
        cv_lolo = [(train, test) for train, test in cv.split(
            X=y_4classes, y=y_4classes, labels=y_4classes)]

        # With sklearn >= 0.17, `clf` can be identified as a regressor, and
        # the scoring metrics can therefore be automatically assigned.
        scorer_regress = None
    else:
        from sklearn.cross_validation import (KFold, StratifiedKFold,
                                              ShuffleSplit, LeaveOneLabelOut)
        cv_shuffle = ShuffleSplit(len(epochs))
        cv_lolo = LeaveOneLabelOut(y_4classes)

        # With sklearn < 0.17, `clf` cannot be identified as a regressor, and
        # therefore the scoring metrics cannot be automatically assigned.
        scorer_regress = mean_squared_error
    # Test default running
    gat = GeneralizationAcrossTime(picks='foo')
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    assert_raises(ValueError, gat.fit, epochs)
    with warnings.catch_warnings(record=True):
        # check classic fit + check manual picks
        gat.picks = [0]
        gat.fit(epochs)
        # check optional y as array
        gat.picks = None
        gat.fit(epochs, y=epochs.events[:, 2])
        # check optional y as list
        gat.fit(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(len(gat.picks_), len(gat.ch_names), 1)
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
        "prediction, no score>", '%s' % gat)
    assert_equal(gat.ch_names, epochs.ch_names)
    # test different predict function:
    gat = GeneralizationAcrossTime(predict_method='decision_function')
    gat.fit(epochs)
    # With classifier, the default cv is StratifiedKFold
    assert_true(gat.cv_.__class__ == StratifiedKFold)
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 15, 14, 1))
    gat.predict_method = 'predict_proba'
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 15, 14, 2))
    gat.predict_method = 'foo'
    assert_raises(NotImplementedError, gat.predict, epochs)
    gat.predict_method = 'predict'
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 15, 14, 1))
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
        "predicted 14 epochs, no score>", "%s" % gat)
    gat.score(epochs)
    assert_true(gat.scorer_.__name__ == 'accuracy_score')
    # check clf / predict_method combinations for which the scoring metrics
    # cannot be inferred.
    gat.scorer = None
    gat.predict_method = 'decision_function'
    assert_raises(ValueError, gat.score, epochs)
    # Check specifying y manually
    gat.predict_method = 'predict'
    gat.score(epochs, y=epochs.events[:, 2])
    gat.score(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
        "predicted 14 epochs,\n scored "
        "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal(
        "<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
        "0.050 (s), length: 0.050 (s), n_time_windows: 15>",
        "%s" % gat.train_times_)
    assert_equal(
        "<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
        "0.050 (s), length: 0.050 (s), n_time_windows: 15 x 15>",
        "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    gat_ = copy.deepcopy(gat)
    with use_log_level('error'):
        assert_raises(ValueError, gat_.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] == gat.y_true_.shape[0] == len(
        gat.y_pred_[0][0]) == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(
        len(gat.train_times_['slices']) == 15 == np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(
        len(gat.test_times_['slices']) == 15 == np.shape(gat.scores_)[0])
    assert_true(
        len(gat.test_times_['slices'][0]) == 15 == np.shape(gat.scores_)[1])

    # Test score_mode
    gat.score_mode = 'foo'
    assert_raises(ValueError, gat.score, epochs)
    gat.score_mode = 'fold-wise'
    scores = gat.score(epochs)
    assert_array_equal(np.shape(scores), [15, 15, 5])
    gat.score_mode = 'mean-sample-wise'
    scores = gat.score(epochs)
    assert_array_equal(np.shape(scores), [15, 15])
    gat.score_mode = 'mean-fold-wise'
    scores = gat.score(epochs)
    assert_array_equal(np.shape(scores), [15, 15])
    gat.predict_mode = 'mean-prediction'
    with warnings.catch_warnings(record=True) as w:
        gat.score(epochs)
        assert_true(
            any("score_mode changed from " in str(ww.message) for ww in w))

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    with warnings.catch_warnings(record=True):  # not vectorizing
        scores = gat.score(epochs)
    assert_true(isinstance(scores, np.ndarray))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check
    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.score(epochs)
    assert_true(len(gat.scores_) == len(gat.estimators_) == 8)  # training time
    assert_equal(len(gat.scores_[0]), 15)  # testing time

    # Test start stop training & test cv without n_fold params
    y_4classes = np.hstack((epochs.events[:7, 2], epochs.events[7:, 2] + 1))
    train_times = dict(start=0.090, stop=0.250)
    gat = GeneralizationAcrossTime(cv=cv_lolo, train_times=train_times)
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=y_4classes)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times_['times'][0], epochs.times[6])
    assert_equal(gat.train_times_['times'][-1], epochs.times[9])

    # Test score without passing epochs & Test diagonal decoding
    gat = GeneralizationAcrossTime(test_times='diagonal')
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.fit(epochs)
    assert_raises(RuntimeError, gat.score)
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.predict(epochs)
    scores = gat.score()
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))
    assert_array_equal(
        [tim for ttime in gat.test_times_['times'] for tim in ttime],
        gat.train_times_['times'])
    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction', cv=2)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    with warnings.catch_warnings(record=True):
        # There are some empty test folds because of n_trials
        gat.predict(epochs[7:])
        gat.score(epochs[7:])

    # Test training time parameters
    gat_ = copy.deepcopy(gat)
    # --- start stop outside time range
    gat_.train_times = dict(start=-999.)
    with use_log_level('error'):
        assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(start=999.)
    assert_raises(ValueError, gat_.fit, epochs)
    # --- impossible slices
    gat_.train_times = dict(step=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=999.)
    assert_raises(ValueError, gat_.fit, epochs)

    # Test testing time parameters
    # --- outside time range
    gat.test_times = dict(start=-999.)
    with warnings.catch_warnings(record=True):  # no epochs in fold
        assert_raises(ValueError, gat.predict, epochs)
    gat.test_times = dict(start=999.)
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat.predict, epochs)
    # --- impossible slices
    gat.test_times = dict(step=.000001)
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat.predict, epochs)
    gat_ = copy.deepcopy(gat)
    gat_.train_times_['length'] = .000001
    gat_.test_times = dict(length=.000001)
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat_.predict, epochs)
    # --- test time region of interest
    gat.test_times = dict(step=.150)
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 5, 14, 1))
    # --- silly value
    gat.test_times = 'foo'
    with warnings.catch_warnings(record=True):  # no test epochs
        assert_raises(ValueError, gat.predict, epochs)
    assert_raises(RuntimeError, gat.score)
    # --- unmatched length between training and testing time
    gat.test_times = dict(length=.150)
    assert_raises(ValueError, gat.predict, epochs)
    # --- irregular length training and testing times
    # 2 estimators, the first one is trained on two successive time samples
    # whereas the second one is trained on a single time sample.
    train_times = dict(slices=[[0, 1], [1]])
    # The first estimator is tested once, the second estimator is tested on
    # two successive time samples.
    test_times = dict(slices=[[[0, 1]], [[0], [1]]])
    gat = GeneralizationAcrossTime(train_times=train_times,
                                   test_times=test_times)
    gat.fit(epochs)
    with warnings.catch_warnings(record=True):  # not vectorizing
        gat.score(epochs)
    assert_array_equal(np.shape(gat.y_pred_[0]), [1, len(epochs), 1])
    assert_array_equal(np.shape(gat.y_pred_[1]), [2, len(epochs), 1])
    # check cannot Automatically infer testing times for adhoc training times
    gat.test_times = None
    assert_raises(ValueError, gat.predict, epochs)

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc, predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    with use_log_level('error'):
        assert_raises(ValueError, gat.score, epochs2)
        gat.score(epochs)
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime(cv=cv_shuffle)
    gat.fit(epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.predict(epochs)
    assert_raises(ValueError, gat.predict, epochs[:10])

    # Make CV with some empty train and test folds:
    # --- empty test fold(s) should warn when gat.predict()
    gat._cv_splits[0] = [gat._cv_splits[0][0], np.empty(0)]
    with warnings.catch_warnings(record=True) as w:
        gat.predict(epochs)
        assert_true(len(w) > 0)
        assert_true(
            any('do not have any test epochs' in str(ww.message) for ww in w))
    # --- empty train fold(s) should raise when gat.fit()
    gat = GeneralizationAcrossTime(cv=[([0], [1]), ([], [0])])
    assert_raises(ValueError, gat.fit, epochs[:2])

    # Check that still works with classifier that output y_pred with
    # shape = (n_trials, 1) instead of (n_trials,)
    if check_version('sklearn', '0.17'):  # no is_regressor before v0.17
        gat = GeneralizationAcrossTime(clf=KernelRidge(), cv=2)
        epochs.crop(None, epochs.times[2])
        gat.fit(epochs)
        # With regression the default cv is KFold and not StratifiedKFold
        assert_true(gat.cv_.__class__ == KFold)
        gat.score(epochs)
        # with regression the default scoring metrics is mean squared error
        assert_true(gat.scorer_.__name__ == 'mean_squared_error')

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2, 4]  # 4 tested
    # nicely ordered labels or not
    le = LabelEncoder()
    y = le.fit_transform(epochs.events[:, 2])
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Univariate and multivariate prediction
    svc = SVC(C=1, kernel='linear', probability=True)
    reg = KernelRidge()

    def scorer_proba(y_true, y_pred):
        return roc_auc_score(y_true, y_pred[:, 0])

    # We re testing 3 scenario: default, classifier + predict_proba, regressor
    scorers = [None, scorer_proba, scorer_regress]
    predict_methods = [None, 'predict_proba', None]
    clfs = [svc, svc, reg]
    # Test all combinations
    for clf, predict_method, scorer in zip(clfs, predict_methods, scorers):
        for y in ys:
            for n_class in n_classes:
                for predict_mode in ['cross-validation', 'mean-prediction']:
                    # Cannot use AUC for n_class > 2
                    if (predict_method == 'predict_proba' and n_class != 2):
                        continue

                    y_ = y % n_class

                    with warnings.catch_warnings(record=True):
                        gat = GeneralizationAcrossTime(
                            cv=2,
                            clf=clf,
                            scorer=scorer,
                            predict_mode=predict_mode)
                        gat.fit(epochs, y=y_)
                        gat.score(epochs, y=y_)

                    # Check that scorer is correctly defined manually and
                    # automatically.
                    scorer_name = gat.scorer_.__name__
                    if scorer is None:
                        if is_classifier(clf):
                            assert_equal(scorer_name, 'accuracy_score')
                        else:
                            assert_equal(scorer_name, 'mean_squared_error')
                    else:
                        assert_equal(scorer_name, scorer.__name__)
Exemple #4
0
def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC
    from sklearn.linear_model import RANSACRegressor, LinearRegression
    from sklearn.preprocessing import LabelEncoder
    from sklearn.metrics import mean_squared_error
    from sklearn.cross_validation import LeaveOneLabelOut

    epochs = make_epochs()

    # Test default running
    gat = GeneralizationAcrossTime(picks='foo')
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    assert_raises(ValueError, gat.fit, epochs)
    with warnings.catch_warnings(record=True):
        # check classic fit + check manual picks
        gat.picks = [0]
        gat.fit(epochs)
        # check optional y as array
        gat.picks = None
        gat.fit(epochs, y=epochs.events[:, 2])
        # check optional y as list
        gat.fit(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(len(gat.picks_), len(gat.ch_names), 1)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
                 "prediction, no score>", '%s' % gat)
    assert_equal(gat.ch_names, epochs.ch_names)
    gat.predict(epochs)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predicted 14 epochs, no score>",
                 "%s" % gat)
    gat.score(epochs)
    gat.score(epochs, y=epochs.events[:, 2])
    gat.score(epochs, y=epochs.events[:, 2].tolist())
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predicted 14 epochs,\n scored "
                 "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.050 (s), length: 0.050 (s), n_time_windows: 15>",
                 "%s" % gat.train_times_)
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.050 (s), length: 0.050 (s), n_time_windows: 15 x 15>",
                 "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    gat_ = copy.deepcopy(gat)
    assert_raises(ValueError, gat_.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] ==
                gat.y_true_.shape[0] ==
                len(gat.y_pred_[0][0]) == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(len(gat.train_times_['slices']) == 15 ==
                np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(len(gat.test_times_['slices']) == 15 ==
                np.shape(gat.scores_)[0])
    assert_true(len(gat.test_times_['slices'][0]) == 15 ==
                np.shape(gat.scores_)[1])

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    scores = gat.score(epochs)
    assert_true(isinstance(scores, list))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check

    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.score(epochs)
    assert_true(len(gat.scores_) == len(gat.estimators_) == 8)  # training time
    assert_equal(len(gat.scores_[0]), 15)  # testing time

    # Test start stop training & test cv without n_fold params
    y_4classes = np.hstack((epochs.events[:7, 2], epochs.events[7:, 2] + 1))
    gat = GeneralizationAcrossTime(cv=LeaveOneLabelOut(y_4classes),
                                   train_times={'start': 0.090, 'stop': 0.250})
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=y_4classes)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times_['times'][0], epochs.times[6])
    assert_equal(gat.train_times_['times'][-1], epochs.times[9])

    # Test score without passing epochs & Test diagonal decoding
    gat = GeneralizationAcrossTime(test_times='diagonal')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    assert_raises(RuntimeError, gat.score)
    gat.predict(epochs)
    scores = gat.score()
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))
    assert_array_equal([tim for ttime in gat.test_times_['times']
                        for tim in ttime], gat.train_times_['times'])

    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    gat.predict(epochs[7:])
    gat.score(epochs[7:])

    # Test training time parameters
    gat_ = copy.deepcopy(gat)
    # --- start stop outside time range
    gat_.train_times = dict(start=-999.)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(start=999.)
    assert_raises(ValueError, gat_.fit, epochs)
    # --- impossible slices
    gat_.train_times = dict(step=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=999.)
    assert_raises(ValueError, gat_.fit, epochs)

    # Test testing time parameters
    # --- outside time range
    gat.test_times = dict(start=-999.)
    assert_raises(ValueError, gat.predict, epochs)
    gat.test_times = dict(start=999.)
    assert_raises(ValueError, gat.predict, epochs)
    # --- impossible slices
    gat.test_times = dict(step=.000001)
    assert_raises(ValueError, gat.predict, epochs)
    gat_ = copy.deepcopy(gat)
    gat_.train_times_['length'] = .000001
    gat_.test_times = dict(length=.000001)
    assert_raises(ValueError, gat_.predict, epochs)
    # --- test time region of interest
    gat.test_times = dict(step=.150)
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 5, 14, 1))
    # --- silly value
    gat.test_times = 'foo'
    assert_raises(ValueError, gat.predict, epochs)
    assert_raises(RuntimeError, gat.score)
    # --- unmatched length between training and testing time
    gat.test_times = dict(length=.150)
    assert_raises(ValueError, gat.predict, epochs)

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc, predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    assert_raises(ValueError, gat.score, epochs2)
    gat.score(epochs)
    scores = sum(scores, [])  # flatten
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.predict(epochs)
    assert_raises(IndexError, gat.predict, epochs[:10])

    # TODO JRK: test GAT with non-exhaustive CV (eg. train on 80%, test on 10%)

    # Check that still works with classifier that output y_pred with
    # shape = (n_trials, 1) instead of (n_trials,)
    gat = GeneralizationAcrossTime(clf=RANSACRegressor(LinearRegression()),
                                   cv=2)
    epochs.crop(None, epochs.times[2])
    gat.fit(epochs)
    gat.predict(epochs)

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2, 4]  # 4 tested
    # nicely ordered labels or not
    le = LabelEncoder()
    y = le.fit_transform(epochs.events[:, 2])
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Univariate and multivariate prediction
    svc = SVC(C=1, kernel='linear')

    class SVC_proba(SVC):
        def predict(self, x):
            probas = super(SVC_proba, self).predict_proba(x)
            return probas[:, 0]

    svcp = SVC_proba(C=1, kernel='linear', probability=True)
    clfs = [svc, svcp]
    scorers = [None, mean_squared_error]
    # Test all combinations
    for clf, scorer in zip(clfs, scorers):
        for y in ys:
            for n_class in n_classes:
                y_ = y % n_class
                with warnings.catch_warnings(record=True):
                    gat = GeneralizationAcrossTime(cv=2, clf=clf,
                                                   scorer=scorer)
                    gat.fit(epochs, y=y_)
                    gat.score(epochs, y=y_)
Exemple #5
0
def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC
    from sklearn.linear_model import RANSACRegressor, LinearRegression
    from sklearn.preprocessing import LabelEncoder
    from sklearn.metrics import mean_squared_error
    from sklearn.cross_validation import LeaveOneLabelOut

    epochs = make_epochs()

    # Test default running
    gat = GeneralizationAcrossTime(picks='foo')
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    assert_raises(ValueError, gat.fit, epochs)
    with warnings.catch_warnings(record=True):
        # check classic fit + check manual picks
        gat.picks = [0]
        gat.fit(epochs)
        # check optional y as array
        gat.picks = None
        gat.fit(epochs, y=epochs.events[:, 2])
        # check optional y as list
        gat.fit(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(len(gat.picks_), len(gat.ch_names), 1)
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
        "prediction, no score>", '%s' % gat)
    assert_equal(gat.ch_names, epochs.ch_names)
    gat.predict(epochs)
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
        "predicted 14 epochs, no score>", "%s" % gat)
    gat.score(epochs)
    gat.score(epochs, y=epochs.events[:, 2])
    gat.score(epochs, y=epochs.events[:, 2].tolist())
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
        "predicted 14 epochs,\n scored "
        "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal(
        "<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
        "0.047 (s), length: 0.047 (s), n_time_windows: 15>",
        "%s" % gat.train_times_)
    assert_equal(
        "<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
        "0.047 (s), length: 0.047 (s), n_time_windows: 15 x 15>",
        "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    gat_ = copy.deepcopy(gat)
    assert_raises(ValueError, gat_.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] == gat.y_true_.shape[0] == len(
        gat.y_pred_[0][0]) == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(
        len(gat.train_times_['slices']) == 15 == np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(
        len(gat.test_times_['slices']) == 15 == np.shape(gat.scores_)[0])
    assert_true(
        len(gat.test_times_['slices'][0]) == 15 == np.shape(gat.scores_)[1])

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    scores = gat.score(epochs)
    assert_true(isinstance(scores, list))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check

    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.score(epochs)
    assert_true(len(gat.scores_) == len(gat.estimators_) == 8)  # training time
    assert_equal(len(gat.scores_[0]), 15)  # testing time

    # Test start stop training & test cv without n_fold params
    y_4classes = np.hstack((epochs.events[:7, 2], epochs.events[7:, 2] + 1))
    gat = GeneralizationAcrossTime(cv=LeaveOneLabelOut(y_4classes),
                                   train_times={
                                       'start': 0.090,
                                       'stop': 0.250
                                   })
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=y_4classes)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times_['times'][0], epochs.times[6])
    assert_equal(gat.train_times_['times'][-1], epochs.times[9])

    # Test score without passing epochs & Test diagonal decoding
    gat = GeneralizationAcrossTime(test_times='diagonal')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    assert_raises(RuntimeError, gat.score)
    gat.predict(epochs)
    scores = gat.score()
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))
    assert_array_equal(
        [tim for ttime in gat.test_times_['times'] for tim in ttime],
        gat.train_times_['times'])

    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    gat.predict(epochs[7:])
    gat.score(epochs[7:])

    # Test training time parameters
    gat_ = copy.deepcopy(gat)
    # --- start stop outside time range
    gat_.train_times = dict(start=-999.)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(start=999.)
    assert_raises(ValueError, gat_.fit, epochs)
    # --- impossible slices
    gat_.train_times = dict(step=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=.000001)
    assert_raises(ValueError, gat_.fit, epochs)
    gat_.train_times = dict(length=999.)
    assert_raises(ValueError, gat_.fit, epochs)

    # Test testing time parameters
    # --- outside time range
    gat.test_times = dict(start=-999.)
    assert_raises(ValueError, gat.predict, epochs)
    gat.test_times = dict(start=999.)
    assert_raises(ValueError, gat.predict, epochs)
    # --- impossible slices
    gat.test_times = dict(step=.000001)
    assert_raises(ValueError, gat.predict, epochs)
    gat_ = copy.deepcopy(gat)
    gat_.train_times_['length'] = .000001
    gat_.test_times = dict(length=.000001)
    assert_raises(ValueError, gat_.predict, epochs)
    # --- test time region of interest
    gat.test_times = dict(step=.150)
    gat.predict(epochs)
    assert_array_equal(np.shape(gat.y_pred_), (15, 5, 14, 1))
    # --- silly value
    gat.test_times = 'foo'
    assert_raises(ValueError, gat.predict, epochs)
    assert_raises(RuntimeError, gat.score)
    # --- unmatched length between training and testing time
    gat.test_times = dict(length=.150)
    assert_raises(ValueError, gat.predict, epochs)

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc, predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    assert_raises(ValueError, gat.score, epochs2)
    gat.score(epochs)
    scores = sum(scores, [])  # flatten
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    assert_raises(ValueError, gat.predict, epochs[:10])

    # Check that still works with classifier that output y_pred with
    # shape = (n_trials, 1) instead of (n_trials,)
    gat = GeneralizationAcrossTime(clf=RANSACRegressor(LinearRegression()),
                                   cv=2)
    epochs.crop(None, epochs.times[2])
    gat.fit(epochs)
    gat.predict(epochs)

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2, 4]  # 4 tested
    # nicely ordered labels or not
    le = LabelEncoder()
    y = le.fit_transform(epochs.events[:, 2])
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Univariate and multivariate prediction
    svc = SVC(C=1, kernel='linear')

    class SVC_proba(SVC):
        def predict(self, x):
            probas = super(SVC_proba, self).predict_proba(x)
            return probas[:, 0]

    svcp = SVC_proba(C=1, kernel='linear', probability=True)
    clfs = [svc, svcp]
    scorers = [None, mean_squared_error]
    # Test all combinations
    for clf, scorer in zip(clfs, scorers):
        for y in ys:
            for n_class in n_classes:
                y_ = y % n_class
                with warnings.catch_warnings(record=True):
                    gat = GeneralizationAcrossTime(cv=2,
                                                   clf=clf,
                                                   scorer=scorer)
                    gat.fit(epochs, y=y_)
                    gat.score(epochs, y=y_)
Exemple #6
0
def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC

    raw = io.Raw(raw_fname, preload=False)
    events = read_events(event_name)
    picks = pick_types(raw.info, meg='mag', stim=False, ecg=False,
                       eog=False, exclude='bads')
    picks = picks[0:2]
    decim = 30

    # Test on time generalization within one condition
    with warnings.catch_warnings(record=True):
        epochs = Epochs(raw, events, event_id, tmin, tmax, picks=picks,
                        baseline=(None, 0), preload=True, decim=decim)
    # Test default running
    gat = GeneralizationAcrossTime()
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
                 "prediction, no score>", '%s' % gat)
    gat.predict(epochs)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predict_type : 'predict' on 15 epochs, no score>",
                 "%s" % gat)
    gat.score(epochs)
    assert_equal("<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
                 "predict_type : 'predict' on 15 epochs,\n scored "
                 "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_type = gat.predict_type
    gat.predict_type = 'foo'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_type = old_type

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.047 (s), length: 0.047 (s), n_time_windows: 15>",
                 "%s" % gat.train_times)
    assert_equal("<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
                 "0.047 (s), length: 0.047 (s), n_time_windows: 15 x 15>",
                 "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    assert_raises(ValueError, gat.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] ==
                gat.y_true_.shape[0] ==
                gat.y_pred_.shape[2] == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(len(gat.train_times['slices']) == 15 ==
                np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(len(gat.test_times_['slices']) == 15 ==
                np.shape(gat.scores_)[0])
    assert_true(len(gat.test_times_['slices'][0]) == 15 ==
                np.shape(gat.scores_)[1])

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    scores = gat.score(epochs)
    assert_true(isinstance(scores, list))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check

    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.score(epochs)
    assert_equal(len(gat.scores_), 8)

    # Test start stop training
    gat = GeneralizationAcrossTime(train_times={'start': 0.090,
                                                'stop': 0.250})
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times['times_'][0], epochs.times[6])
    assert_equal(gat.train_times['times_'][-1], epochs.times[9])

    # Test score without passing epochs
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    assert_raises(RuntimeError, gat.score)
    gat.predict(epochs, test_times='diagonal')  # Test diagonal decoding
    scores = gat.score()
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))

    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    gat.predict(epochs[7:])
    assert_raises(ValueError, gat.predict, epochs, test_times='hahahaha')
    assert_raises(RuntimeError, gat.score)
    gat.score(epochs[7:])

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc, predict_type='predict_proba',
                                   predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    assert_raises(ValueError, gat.score, epochs2)
    gat.score(epochs)
    scores = sum(scores, [])  # flatten
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # test various predict_type
    gat = GeneralizationAcrossTime(clf=svc, predict_type="predict_proba")
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    # check that 2 class probabilistic estimates are [p, 1-p]
    assert_true(gat.y_pred_.shape[3] == 2)
    gat.score(epochs)
    # check that continuous prediction leads to AUC rather than accuracy
    assert_true("roc_auc_score" in '%s' % gat.scorer_)

    gat = GeneralizationAcrossTime(predict_type="decision_function")
    # XXX Sklearn doesn't like non-binary inputs. We could binarize the data,
    # or change Sklearn default behavior
    epochs.events[:, 2][epochs.events[:, 2] == 3] = 0
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    # check that 2 class non-probabilistic continuous estimates are [distance]
    assert_true(gat.y_pred_.shape[3] == 1)
    gat.score(epochs)
    # check that continuous prediction leads to AUC rather than accuracy
    assert_true("roc_auc_score" in '%s' % gat.scorer_)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    assert_raises(ValueError, gat.predict, epochs[:10])

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2]  # 4 tested
    # nicely ordered labels or not
    y = epochs.events[:, 2]
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Classifier and regressor
    svc = SVC(C=1, kernel='linear', probability=True)
    clfs = [svc]  # SVR tested
    # Continuous, and probabilistic estimate
    predict_types = ['predict_proba', 'decision_function']
    # Test all combinations
    for clf_n, clf in enumerate(clfs):
        for y in ys:
            for n_class in n_classes:
                for pt in predict_types:
                    y_ = y % n_class
                    with warnings.catch_warnings(record=True):
                        gat = GeneralizationAcrossTime(
                            cv=2, clf=clf, predict_type=pt)
                        gat.fit(epochs, y=y_)
                        gat.score(epochs, y=y_)
Exemple #7
0
				stim_list_rsvp[itrl,istim] = 3
			elif 'body' in rsvpfile:
				stim_list_rsvp[itrl,istim] = 4

	# get lag indices
	lag = mat['output']['target'][0][0][0][0][0][0]
	R1 = mat['output']['response'][0][0][0][0][3][0][0][0][0]
	R2 = mat['output']['response'][0][0][0][0][4][0][0][0]
	ulag = np.unique(lag)
	n_lag = len(ulag)
	# offset = [-1, 0, 1]

	# decoding
	epochs = epochs.decimate(decim)
	n_te = len(epochs.times)
	gat.predict_mode = 'mean-prediction' # generalization across conditions so no cross validation here.

	# compute scores for each stimulus
	rsvp_score_all = np.zeros((n_tr, n_te, n_stim))
	rsvp_score_lag = np.zeros((n_tr, n_te, n_stim, n_lag))
	rsvp_score_offset0_lag = np.zeros((n_tr, n_te, n_stim, n_lag))
	rsvp_score_offset_1_lag = np.zeros((n_tr, n_te, n_stim, n_lag))
	rsvp_score_offset1_lag = np.zeros((n_tr, n_te, n_stim, n_lag))
	for istim in range(n_stim):
		# compute scores across all trials
		s = gat.score(epochs, stim_list_rsvp[:,istim]) # compute predictions as well.
		s = np.array(s)
		rsvp_score_all[:,:,istim] = s

		# compute scores for lags
		for ilag in range(len(ulag)):
Exemple #8
0
def test_generalization_across_time():
    """Test time generalization decoding
    """
    from sklearn.svm import SVC

    raw = io.Raw(raw_fname, preload=False)
    events = read_events(event_name)
    picks = pick_types(raw.info,
                       meg='mag',
                       stim=False,
                       ecg=False,
                       eog=False,
                       exclude='bads')
    picks = picks[0:2]
    decim = 30

    # Test on time generalization within one condition
    with warnings.catch_warnings(record=True):
        epochs = Epochs(raw,
                        events,
                        event_id,
                        tmin,
                        tmax,
                        picks=picks,
                        baseline=(None, 0),
                        preload=True,
                        decim=decim)
    # Test default running
    gat = GeneralizationAcrossTime()
    assert_equal("<GAT | no fit, no prediction, no score>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), no "
        "prediction, no score>", '%s' % gat)
    gat.predict(epochs)
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
        "predict_type : 'predict' on 15 epochs, no score>", "%s" % gat)
    gat.score(epochs)
    assert_equal(
        "<GAT | fitted, start : -0.200 (s), stop : 0.499 (s), "
        "predict_type : 'predict' on 15 epochs,\n scored "
        "(accuracy_score)>", "%s" % gat)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs, y=epochs.events[:, 2])

    old_type = gat.predict_type
    gat.predict_type = 'foo'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_type = old_type

    old_mode = gat.predict_mode
    gat.predict_mode = 'super-foo-mode'
    assert_raises(ValueError, gat.predict, epochs)
    gat.predict_mode = old_mode

    gat.score(epochs, y=epochs.events[:, 2])
    assert_true("accuracy_score" in '%s' % gat.scorer_)
    epochs2 = epochs.copy()

    # check _DecodingTime class
    assert_equal(
        "<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
        "0.047 (s), length: 0.047 (s), n_time_windows: 15>",
        "%s" % gat.train_times)
    assert_equal(
        "<DecodingTime | start: -0.200 (s), stop: 0.499 (s), step: "
        "0.047 (s), length: 0.047 (s), n_time_windows: 15 x 15>",
        "%s" % gat.test_times_)

    # the y-check
    gat.predict_mode = 'mean-prediction'
    epochs2.events[:, 2] += 10
    assert_raises(ValueError, gat.score, epochs2)
    gat.predict_mode = 'cross-validation'

    # Test basics
    # --- number of trials
    assert_true(gat.y_train_.shape[0] == gat.y_true_.shape[0] ==
                gat.y_pred_.shape[2] == 14)
    # ---  number of folds
    assert_true(np.shape(gat.estimators_)[1] == gat.cv)
    # ---  length training size
    assert_true(
        len(gat.train_times['slices']) == 15 == np.shape(gat.estimators_)[0])
    # ---  length testing sizes
    assert_true(
        len(gat.test_times_['slices']) == 15 == np.shape(gat.scores_)[0])
    assert_true(
        len(gat.test_times_['slices'][0]) == 15 == np.shape(gat.scores_)[1])

    # Test longer time window
    gat = GeneralizationAcrossTime(train_times={'length': .100})
    with warnings.catch_warnings(record=True):
        gat2 = gat.fit(epochs)
    assert_true(gat is gat2)  # return self
    assert_true(hasattr(gat2, 'cv_'))
    assert_true(gat2.cv_ != gat.cv)
    scores = gat.score(epochs)
    assert_true(isinstance(scores, list))  # type check
    assert_equal(len(scores[0]), len(scores))  # shape check

    assert_equal(len(gat.test_times_['slices'][0][0]), 2)
    # Decim training steps
    gat = GeneralizationAcrossTime(train_times={'step': .100})
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    gat.score(epochs)
    assert_equal(len(gat.scores_), 8)

    # Test start stop training
    gat = GeneralizationAcrossTime(train_times={'start': 0.090, 'stop': 0.250})
    # predict without fit
    assert_raises(RuntimeError, gat.predict, epochs)
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.score(epochs)
    assert_equal(len(gat.scores_), 4)
    assert_equal(gat.train_times['times_'][0], epochs.times[6])
    assert_equal(gat.train_times['times_'][-1], epochs.times[9])

    # Test diagonal decoding
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    scores = gat.score(epochs, test_times='diagonal')
    assert_true(scores is gat.scores_)
    assert_equal(np.shape(gat.scores_), (15, 1))

    # Test generalization across conditions
    gat = GeneralizationAcrossTime(predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs[0:6])
    gat.predict(epochs[7:])
    assert_raises(ValueError, gat.predict, epochs, test_times='hahahaha')
    gat.score(epochs[7:])

    svc = SVC(C=1, kernel='linear', probability=True)
    gat = GeneralizationAcrossTime(clf=svc,
                                   predict_type='predict_proba',
                                   predict_mode='mean-prediction')
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)

    # sklearn needs it: c.f.
    # https://github.com/scikit-learn/scikit-learn/issues/2723
    # and http://bit.ly/1u7t8UT
    assert_raises(ValueError, gat.score, epochs2)
    gat.score(epochs)
    scores = sum(scores, [])  # flatten
    assert_true(0.0 <= np.min(scores) <= 1.0)
    assert_true(0.0 <= np.max(scores) <= 1.0)

    # test various predict_type
    gat = GeneralizationAcrossTime(clf=svc, predict_type="predict_proba")
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    # check that 2 class probabilistic estimates are [p, 1-p]
    assert_true(gat.y_pred_.shape[3] == 2)
    gat.score(epochs)
    # check that continuous prediction leads to AUC rather than accuracy
    assert_true("roc_auc_score" in '%s' % gat.scorer_)

    gat = GeneralizationAcrossTime(predict_type="decision_function")
    # XXX Sklearn doesn't like non-binary inputs. We could binarize the data,
    # or change Sklearn default behavior
    epochs.events[:, 2][epochs.events[:, 2] == 3] = 0
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    # check that 2 class non-probabilistic continuous estimates are [distance]
    assert_true(gat.y_pred_.shape[3] == 1)
    gat.score(epochs)
    # check that continuous prediction leads to AUC rather than accuracy
    assert_true("roc_auc_score" in '%s' % gat.scorer_)

    # Test that gets error if train on one dataset, test on another, and don't
    # specify appropriate cv:
    gat = GeneralizationAcrossTime()
    with warnings.catch_warnings(record=True):
        gat.fit(epochs)
    gat.predict(epochs)
    assert_raises(ValueError, gat.predict, epochs[:10])

    # Test combinations of complex scenarios
    # 2 or more distinct classes
    n_classes = [2]  # 4 tested
    # nicely ordered labels or not
    y = epochs.events[:, 2]
    y[len(y) // 2:] += 2
    ys = (y, y + 1000)
    # Classifier and regressor
    svc = SVC(C=1, kernel='linear', probability=True)
    clfs = [svc]  # SVR tested
    # Continuous, and probabilistic estimate
    predict_types = ['predict_proba', 'decision_function']
    # Test all combinations
    for clf_n, clf in enumerate(clfs):
        for y in ys:
            for n_class in n_classes:
                for pt in predict_types:
                    y_ = y % n_class
                    with warnings.catch_warnings(record=True):
                        gat = GeneralizationAcrossTime(cv=2,
                                                       clf=clf,
                                                       predict_type=pt)
                        gat.fit(epochs, y=y_)
                        gat.score(epochs, y=y_)