docs: private int getClusterBoundary(Relation<O> relation, List<? extends Cluster<MeanModel>> clusters) {
      int totalSize = relation.size();
      int clusterBoundary = clusters.size() - 1;
      int cumulativeSize = 0;
      for(int i = 0; i < clusters.size() - 1; i++) {
        cumulativeSize += clusters.get(i).size();
  
        // Given majority covered by large cluster
        if(cumulativeSize >= totalSize * alpha) {
          clusterBoundary = i;
          break;
        }
  
        // Relative difference in cluster size between two consecutive clusters
        if(clusters.get(i).size() / (double) clusters.get(i + 1).size() >= beta) {
          clusterBoundary = i;
          break;
        }
      }
      return clusterBoundary;
    }