* Double#NEGATIVE_INFINITY}, or {@link Double#NaN}) then the result is {@link Double#NaN}.
   *
   * @throws IllegalStateException if the dataset is empty or contains a single value
   */
  public double sampleStandardDeviation() {
    return Math.sqrt(sampleVariance());
  }

  /**
   * Returns the lowest value in the dataset. The count must be non-zero.
   *
   * <h3>Non-finite values</h3>
   *