private static String pluralityValue(List<Instance> instances, DataSet train){
        int[] labelsCount = new int[train.labels.size()];
        for(Instance instance : instances){
            labelsCount[instance.label]++;
        }
        int maxLabelCount = -1;
        int maxLabelIndex = -1;
        for(int i = 0; i < labelsCount.length; i++){
            if(labelsCount[i] > maxLabelCount){
                maxLabelCount = labelsCount[i];
                maxLabelIndex = i;
            }
        }
        return train.labels.get(maxLabelIndex);
    }