java - java中用于社区检测的归一化互信息植入图范围不在0到1之间

Question

我编写了一个程序来计算标准化互信息以评估社区检测。但我得到的 nmi 值高于 1。通常它应该在 0 和 1 之间。我在http://nlp.stanford.edu/IR-book/html/htmledition/evaluation-of-clustering-1.html中实现公式

我的代码有什么问题？

这是我的代码：

    public void calNmi(int size, Map<Integer, List<Integer>> realcom, Map<Integer, List<Integer>> foundcom){

    List<Double> hf = new ArrayList<>();
    List<Double> hr = new ArrayList<>();
    double I = 0;

    for (Map.Entry<Integer, List<Integer>> found : foundcom.entrySet()) {
        int comSize = found.getValue().size();
        double p = (double) comSize/size;
        hf.add( -p * (Math.log(p)/Math.log(2)));
     }


    for (Map.Entry<Integer, List<Integer>> real : realcom.entrySet()) {
        int comSize = real.getValue().size();
        double p = (double) comSize/size;
        hr.add(-p * (Math.log(p)/Math.log(2)));
    }

    int i =0;
    for (Map.Entry<Integer, List<Integer>> real : realcom.entrySet()) {
        if(i%100 == 0){
            System.out.println(i);
        }
        List<Integer> rCom = real.getValue();
        double pr = (double) rCom.size()/size;
        for (Map.Entry<Integer, List<Integer>> found : foundcom.entrySet()) {
            List<Integer> fCom = found.getValue();
            double pf = (double) fCom.size()/size;
            int intersect = foundIntersect(rCom, fCom);
            if(intersect != 0) {
                double p = (double) intersect / size;
                I += p * (Math.log(p / (pr * pf))) / Math.log(2);
            }
        }
        i++;
    }
    double sumH  = 0;
    for (Double sumh : hr) {
        sumH += sumh;
    }
    double sumF = 0;
    for (Double sumf : hf) {
        sumF += sumf;
    }
    System.out.println("I = " + I + " hf = "+ sumF + " hr " + sumH);
    double nmi = (2 * I)/(sumF + sumH);
    System.out.println("nmi = " + nmi);

}

private int foundIntersect(List<Integer> rCom, List<Integer> fCom) {
    int count = 0;
    for (Integer r : rCom) {
        if(fCom.contains(r)) {
            count++;
        }
    }
    return count;
}