protected void discoverSpecificComments(String similarityFile) {
		System.out.println("topic similarity");

		try {
			PrintWriter pw = new PrintWriter(new File(similarityFile));

			for (_Doc doc : m_trainSet) {
				if (doc instanceof _ParentDoc) {
					pw.print(doc.getName() + "\t");
					double stnTopicSimilarity = 0.0;
					double docTopicSimilarity = 0.0;
					for (_ChildDoc cDoc : ((_ParentDoc) doc).m_childDocs) {
						pw.print(cDoc.getName() + ":");

						docTopicSimilarity = computeSimilarity(
								((_ParentDoc) doc).m_topics, cDoc.m_topics);
						pw.print(docTopicSimilarity);
						for (_Stn stnObj : doc.getSentences()) {

							stnTopicSimilarity = computeSimilarity(
									stnObj.m_topics, cDoc.m_topics);

							pw.print(":" + (stnObj.getIndex() + 1) + ":"
									+ stnTopicSimilarity);
						}
						pw.print("\t");
					}
					pw.println();
				}
			}
			pw.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		}
	}