def compute_metrics(truth_file_stream, prediction_file_stream) -> Dict[str, Dict[str, float]]:
    truth_probabilities = parse_csv(truth_file_stream, CATEGORIES)
    prediction_probabilities = parse_csv(prediction_file_stream, CATEGORIES)

    exclude_rows(truth_probabilities, EXCLUDE_LABELS)
    exclude_rows(prediction_probabilities, EXCLUDE_LABELS)

    validate_rows(truth_probabilities, prediction_probabilities)

    sort_rows(truth_probabilities)
    sort_rows(prediction_probabilities)

    scores: Dict[str, Dict[str, float]] = {}
    for category in CATEGORIES:
        truth_category_probabilities: pd.Series = truth_probabilities[category]
        prediction_category_probabilities: pd.Series = prediction_probabilities[category]

        truth_binary_values: pd.Series = truth_category_probabilities.gt(0.5)
        prediction_binary_values: pd.Series = prediction_category_probabilities.gt(0.5)

        category_cm = create_binary_confusion_matrix(
            truth_binary_values=truth_binary_values.to_numpy(),
            prediction_binary_values=prediction_binary_values.to_numpy(),
            name=category,
        )

        scores[category] = {
            'accuracy': metrics.binary_accuracy(category_cm),
            'sensitivity': metrics.binary_sensitivity(category_cm),
            'specificity': metrics.binary_specificity(category_cm),
            'dice': metrics.binary_dice(category_cm),
            'ppv': metrics.binary_ppv(category_cm),
            'npv': metrics.binary_npv(category_cm),
            'auc': metrics.auc(truth_category_probabilities, prediction_category_probabilities),
            'auc_sens_80': metrics.auc_above_sensitivity(
                truth_category_probabilities, prediction_category_probabilities, 0.80
            ),
            'ap': metrics.average_precision(
                truth_category_probabilities, prediction_category_probabilities
            ),
        }

    # Compute averages for all per-category metrics
    per_category_metrics: ValuesView[str] = next(iter(scores.values())).keys()
    scores['macro_average'] = {
        metric: float(np.mean([scores[category][metric] for category in CATEGORIES]))
        for metric in per_category_metrics
    }

    # Compute multi-category aggregate metrics
    scores['aggregate'] = {
        'balanced_accuracy': metrics.balanced_multiclass_accuracy(
            truth_probabilities, prediction_probabilities
        )
    }

    return scores
Example #2
0
    def from_stream(
        cls, truth_file_stream: TextIO, prediction_file_stream: TextIO
    ):
        truth_probabilities, truth_weights = parse_truth_csv(truth_file_stream)
        categories = truth_probabilities.columns
        prediction_probabilities = parse_csv(prediction_file_stream, categories)

        validate_rows(truth_probabilities, prediction_probabilities)

        sort_rows(truth_probabilities)
        sort_rows(prediction_probabilities)

        score = cls(truth_probabilities, prediction_probabilities, truth_weights)
        return score
Example #3
0
def test_validate_rows_missing_images(categories):
    truth_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
         [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123', 'ISIC_0000124'],
        columns=categories,
    )
    prediction_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
         [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123', 'ISIC_0000124'],
        columns=categories,
    )
    load_csv.validate_rows(truth_probabilities, prediction_probabilities)

    truth_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
         [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123', 'ISIC_0000124'],
        columns=categories,
    )
    prediction_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123'],
        columns=categories)
    with pytest.raises(ScoreException) as exc_info:
        load_csv.validate_rows(truth_probabilities, prediction_probabilities)
    assert "Missing images in CSV: ['ISIC_0000124']." == str(exc_info.value)

    truth_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
         [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123', 'ISIC_0000124'],
        columns=categories,
    )
    prediction_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000120'],
        columns=categories)
    with pytest.raises(ScoreException) as exc_info:
        load_csv.validate_rows(truth_probabilities, prediction_probabilities)
    assert "Missing images in CSV: ['ISIC_0000123', 'ISIC_0000124']." == str(
        exc_info.value)

    truth_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
         [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123', 'ISIC_0000124'],
        columns=categories,
    )
    prediction_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
         [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0]],
        index=['ISIC_0000123', 'ISIC_0000125'],
        columns=categories,
    )
    with pytest.raises(ScoreException) as exc_info:
        load_csv.validate_rows(truth_probabilities, prediction_probabilities)
    assert "Missing images in CSV: ['ISIC_0000124']." == str(exc_info.value)
Example #4
0
def test_validate_rows_extra_images(categories):
    truth_probabilities = pd.DataFrame(
        [[1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]], index=['ISIC_0000123'], columns=categories
    )
    prediction_probabilities = pd.DataFrame(
        [
            [1.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
            [0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 0.0],
            [0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0],
        ],
        index=['ISIC_0000123', 'ISIC_0000126', 'ISIC_0000127'],
        columns=categories,
    )
    with pytest.raises(ScoreException) as exc_info:
        load_csv.validate_rows(truth_probabilities, prediction_probabilities)
    assert 'Extra images in CSV: [\'ISIC_0000126\', \'ISIC_0000127\'].' == str(exc_info.value)
Example #5
0
def compute_metrics(truth_file_stream, prediction_file_stream) -> ScoresType:
    truth_probabilities, truth_weights = parse_truth_csv(truth_file_stream)
    categories = truth_probabilities.columns
    prediction_probabilities = parse_csv(prediction_file_stream, categories)

    validate_rows(truth_probabilities, prediction_probabilities)

    sort_rows(truth_probabilities)
    sort_rows(prediction_probabilities)

    scores: ScoresType = {}
    for category in categories:
        truth_category_probabilities: pd.Series = truth_probabilities[category]
        prediction_category_probabilities: pd.Series = prediction_probabilities[
            category]

        truth_binary_values: pd.Series = truth_category_probabilities.gt(0.5)
        prediction_binary_values: pd.Series = prediction_category_probabilities.gt(
            0.5)

        category_cm = create_binary_confusion_matrix(
            truth_binary_values=truth_binary_values.to_numpy(),
            prediction_binary_values=prediction_binary_values.to_numpy(),
            weights=truth_weights.score_weight.to_numpy(),
            name=category,
        )

        scores[category] = {
            'accuracy':
            metrics.binary_accuracy(category_cm),
            'sensitivity':
            metrics.binary_sensitivity(category_cm),
            'specificity':
            metrics.binary_specificity(category_cm),
            'dice':
            metrics.binary_dice(category_cm),
            'ppv':
            metrics.binary_ppv(category_cm),
            'npv':
            metrics.binary_npv(category_cm),
            'auc':
            metrics.auc(
                truth_category_probabilities,
                prediction_category_probabilities,
                truth_weights.score_weight,
            ),
            'auc_sens_80':
            metrics.auc_above_sensitivity(
                truth_category_probabilities,
                prediction_category_probabilities,
                truth_weights.score_weight,
                0.80,
            ),
            'ap':
            metrics.average_precision(
                truth_category_probabilities,
                prediction_category_probabilities,
                truth_weights.score_weight,
            ),
            'roc':
            metrics.roc(
                truth_category_probabilities,
                prediction_category_probabilities,
                truth_weights.score_weight,
            ),
        }

    # Compute averages for all per-category metrics
    per_category_metrics: KeysView[str] = next(iter(scores.values())).keys()
    scores['macro_average'] = {
        metric:
        float(np.mean([scores[category][metric] for category in categories]))
        for metric in per_category_metrics if metric != 'roc'
    }

    # Compute multi-category aggregate metrics
    scores['aggregate'] = {
        'balanced_accuracy':
        metrics.balanced_multiclass_accuracy(truth_probabilities,
                                             prediction_probabilities,
                                             truth_weights.score_weight)
    }

    scores['overall'] = scores['aggregate']['balanced_accuracy']
    scores['validation'] = metrics.balanced_multiclass_accuracy(
        truth_probabilities, prediction_probabilities,
        truth_weights.validation_weight)

    return scores