double upperValue = PSEUDORANDOM_DATASET_SORTED.get(positionCeil);
      return (lowerValue + upperValue) / 2.0;
    }
  }

  public void testPercentiles_index_compute_doubleCollection() {
    for (int index = 0; index <= 100; index++) {
      assertWithMessage("quantile at index " + index)
          .that(percentiles().index(index).compute(PSEUDORANDOM_DATASET))