code: public double calculateAverageAuc() {
          double ret = 0.0;
          for (int i = 0; i < numLabels(); i++) {
              ret += calculateAUC(i);
          }
  
          return ret / (double) numLabels();
      }
docs: Macro-average AUC for all outcomes
  @return the (macro-)average AUC for all outcomes.