docs: public static Statistics statisticsFor( Statistics[] statistics ) {
          int length = statistics.length;
          if (length == 0) return EMPTY_STATISTICS;
          if (length == 1) return statistics[0] != null ? statistics[0] : EMPTY_STATISTICS;
          int count = 0;
          long max = Long.MIN_VALUE;
          long min = Long.MAX_VALUE;
          double mean = 0.0d;
          double variance = 0.0d;
          // Compute the min, max, and mean ...
          for (Statistics stat : statistics) {
              if (stat == null) continue;
              count += stat.getCount();
              max = Math.max(max, stat.getMaximum());
              min = Math.min(min, stat.getMinimum());
              mean = mean + (stat.getMean() * stat.getCount());
          }
          mean = mean / count;
  
          // Compute the new variance using the new mean ...
          double meanDelta = 0.0d;
          for (Statistics stat : statistics) {
              if (stat == null) continue;
              meanDelta = stat.getMean() - mean;
              variance = variance + (stat.getCount() * (stat.getVariance() + (meanDelta * meanDelta)));
          }
          return new StatisticsImpl(count, min, max, mean, variance);
      }