assertEquivalent(Stats.meanOf(array), stream(array).average().getAsDouble());
      // instance methods on Stats vs instance methods on DoubleSummaryStatistics
      DoubleSummaryStatistics streamStats = stream(array).summaryStatistics();
      assertThat(stats.count()).isEqualTo(streamStats.getCount());
      assertEquivalent(stats.mean(), streamStats.getAverage());
      assertEquivalent(stats.sum(), streamStats.getSum());