@Test
public void testScore() {

    Recall<Integer> scoreCalculator = new Recall<>(1);
    LabelPairCursor<Integer> cursor = new TestLabelPairCursor<>(
        Arrays.asList(1, 0, 1, 0, 1, 0),
        Arrays.asList(1, 0, 0, 1, 1, 0)
    );
    double score = scoreCalculator.score(cursor.iterator());
    assertEquals((double)2 / 3, score, 1e-12);
}