public void calculateMultinomialProbability() {
		double denominator = voca.size();
		for (String token : wordCounts.keySet()) {
			denominator += wordCounts.get(token);
		}

		for (int token = 1; token <= voca.size(); token++) {

			double numerator = 1.0;
			// calculate the probability
			boolean contain = wordCounts.containsKey(Integer.toString(token));
			if (contain) {
				numerator += wordCounts.get(token);
			}
			multinominalProbabilities.put(Integer.toString(token), (numerator / denominator));

		}

	}