FileOutputStream meanVarFile = new FileOutputStream(new File(
"mean-var-pair-trec8-mu=0"));
PrintWriter logger = new PrintWriter(meanVarFile, true);
String sep = " \t ";
DocNameExtractor xt = new DocNameExtractor(docNameField);
TopDocsMeanVariance f_td = td;
MeanVarianceScoreDoc temp[] = f_td.MeanVariancescoreDocs;
for (int d = 0; d < temp.length; d++) {
for (int j = d + 1; j < temp.length; j++) {
double rou = correlation(temp[d].doc, temp[j].doc);
String docName1 = xt.docName(searcher, temp[d].doc);