def METHOD_NAME(df, selection):
    if selection is None:
        vaex_score = df.ml.metrics.matthews_correlation_coefficient(df.x, df.y)
        sklearn_score = metrics.matthews_corrcoef(df.x.values, df.y.values)
        assert vaex_score == sklearn_score
    else:
        vaex_score = df.ml.metrics.matthews_correlation_coefficient(df.x, df.y, selection=selection)
        for i, sel in enumerate(selection):
            sklearn_score = metrics.matthews_corrcoef(df.filter(sel).x.values, df.filter(sel).y.values)
            assert vaex_score[i] == sklearn_score