Exemple #1
0
  // 构造一个tri-trainer分类器。
  public Tritrainer(
      String classifier, String trainingIns_File, String testIns_File, double precentage) {
    try {
      this.classifier1 = (Classifier) Class.forName(classifier).newInstance();
      this.classifier2 = (Classifier) Class.forName(classifier).newInstance();
      this.classifier3 = (Classifier) Class.forName(classifier).newInstance();

      Instances trainingInstances = Util.getInstances(trainingIns_File);

      // 将trainIns_File按照precentage和(1-precentage)的比例切割成labeledIns和unlabeledIns;
      int length = trainingInstances.numInstances();
      int i = new Double(length * precentage).intValue();
      labeledIns = new Instances(trainingInstances, 0);
      for (int j = 0; j < i; j++) {
        labeledIns.add(trainingInstances.firstInstance());
        trainingInstances.delete(0);
      }
      unlabeledIns = trainingInstances;
      testIns = Util.getInstances(testIns_File);

      Init();
    } catch (Exception e) {

    }
  }
Exemple #2
0
 // 将样本集中裁剪提取成m个样本组成的集合;
 public void SubSample(Instances inst, int m) {
   inst.randomize(new Random());
   while (inst.numInstances() != m) {
     inst.delete(0);
   }
   // System.out.println("subsample:=" + inst.numInstances() + " m:=" + m );
 }
Exemple #3
0
 /**
  * Removes a specified number of instances from the given set of instances.
  *
  * @param data given instances
  * @param numRemove number of instances to delete from the given instances
  */
 protected void removeInstances(Instances data, int numRemove) {
   int num = data.numInstances();
   for (int i = num - 1; i > num - 1 - numRemove; i--) {
     data.delete(i);
   }
 }
Exemple #4
0
  public void findAndSetSupportBoundForKnownAntecedents(
      Instances thisClassifiersExtension, boolean allWeightsAreOne) {
    if (m_Antds == null) return;

    double maxPurity = Double.NEGATIVE_INFINITY;
    boolean[] finishedAntecedents = new boolean[m_Antds.size()];
    int numFinishedAntecedents = 0;

    while (numFinishedAntecedents < m_Antds.size()) {
      double maxPurityOfAllAntecedents = Double.NEGATIVE_INFINITY;
      int bestAntecedentsIndex = -1;
      double bestSupportBoundForAllAntecedents = Double.NaN;

      Instances ext = new Instances(thisClassifiersExtension, 0);
      for (int j = 0; j < m_Antds.size(); j++) {
        if (finishedAntecedents[j]) continue;

        ext = new Instances(thisClassifiersExtension);
        /*
         * Remove instances which are not relevant, because they are not covered
         * by the _other_ antecedents.
         */
        for (int k = 0; k < m_Antds.size(); k++) {
          if (k == j) continue;
          Antd exclusionAntd = ((Antd) m_Antds.elementAt(k));
          for (int y = 0; y < ext.numInstances(); y++) {
            if (exclusionAntd.covers(ext.instance(y)) == 0) {
              ext.delete(y--);
            }
          }
        }

        if (ext.attribute(((Antd) m_Antds.elementAt(j)).att.index()).isNumeric()
            && ext.numInstances() > 0) {
          NumericAntd currentAntd = (NumericAntd) ((NumericAntd) m_Antds.elementAt(j)).copy();
          currentAntd.fuzzyYet = true;
          ext.deleteWithMissing(currentAntd.att.index());

          double sumOfWeights = ext.sumOfWeights();
          if (!Utils.gr(sumOfWeights, 0.0)) return;

          ext.sort(currentAntd.att.index());

          double maxPurityForThisAntecedent = 0;
          double bestFoundSupportBound = Double.NaN;

          double lastAccu = 0;
          double lastCover = 0;
          // Test all possible edge points
          if (currentAntd.value == 0) {
            for (int k = 1; k < ext.numInstances(); k++) {
              // break the loop if there is no gain (only works when all instances have weight 1)
              if ((lastAccu + (ext.numInstances() - k - 1))
                          / (lastCover + (ext.numInstances() - k - 1))
                      < maxPurityForThisAntecedent
                  && allWeightsAreOne) {
                break;
              }

              // Bag 1
              if (currentAntd.splitPoint < ext.instance(k).value(currentAntd.att.index())
                  && ext.instance(k).value(currentAntd.att.index())
                      != ext.instance(k - 1).value(currentAntd.att.index())) {
                currentAntd.supportBound = ext.instance(k).value(currentAntd.att.index());

                double[] accuArray = new double[ext.numInstances()];
                double[] coverArray = new double[ext.numInstances()];
                for (int i = 0; i < ext.numInstances(); i++) {
                  coverArray[i] = ext.instance(i).weight();
                  double coverValue = currentAntd.covers(ext.instance(i));
                  if (coverArray[i] >= coverValue * ext.instance(i).weight()) {
                    coverArray[i] = coverValue * ext.instance(i).weight();
                    if (ext.instance(i).classValue() == m_Consequent) {
                      accuArray[i] = coverValue * ext.instance(i).weight();
                    }
                  }
                }

                double purity = (Utils.sum(accuArray)) / (Utils.sum(coverArray));
                if (purity >= maxPurityForThisAntecedent) {
                  maxPurityForThisAntecedent = purity;
                  bestFoundSupportBound = currentAntd.supportBound;
                }
                lastAccu = Utils.sum(accuArray);
                lastCover = Utils.sum(coverArray);
              }
            }
          } else {
            for (int k = ext.numInstances() - 2; k >= 0; k--) {
              // break the loop if there is no gain (only works when all instances have weight 1)
              if ((lastAccu + (k)) / (lastCover + (k)) < maxPurityForThisAntecedent
                  && allWeightsAreOne) {
                break;
              }
              // Bag 2
              if (currentAntd.splitPoint > ext.instance(k).value(currentAntd.att.index())
                  && ext.instance(k).value(currentAntd.att.index())
                      != ext.instance(k + 1).value(currentAntd.att.index())) {
                currentAntd.supportBound = ext.instance(k).value(currentAntd.att.index());

                double[] accuArray = new double[ext.numInstances()];
                double[] coverArray = new double[ext.numInstances()];
                for (int i = 0; i < ext.numInstances(); i++) {
                  coverArray[i] = ext.instance(i).weight();
                  double coverValue = currentAntd.covers(ext.instance(i));
                  if (coverArray[i] >= coverValue * ext.instance(i).weight()) {
                    coverArray[i] = coverValue * ext.instance(i).weight();
                    if (ext.instance(i).classValue() == m_Consequent) {
                      accuArray[i] = coverValue * ext.instance(i).weight();
                    }
                  }
                }

                double purity = (Utils.sum(accuArray)) / (Utils.sum(coverArray));
                if (purity >= maxPurityForThisAntecedent) {
                  maxPurityForThisAntecedent = purity;
                  bestFoundSupportBound = currentAntd.supportBound;
                }
                lastAccu = Utils.sum(accuArray);
                lastCover = Utils.sum(coverArray);
              }
            }
          }

          if (maxPurityForThisAntecedent > maxPurityOfAllAntecedents) {
            bestAntecedentsIndex = j;
            bestSupportBoundForAllAntecedents = bestFoundSupportBound;
            maxPurityOfAllAntecedents = maxPurityForThisAntecedent;
          }
        } else {
          // Nominal Antd
          finishedAntecedents[j] = true;
          numFinishedAntecedents++;
          continue;
        }
      }

      if (bestAntecedentsIndex == -1) {
        return;
      }

      if (maxPurity <= maxPurityOfAllAntecedents) {
        if (Double.isNaN(bestSupportBoundForAllAntecedents)) {
          ((NumericAntd) m_Antds.elementAt(bestAntecedentsIndex)).supportBound =
              ((NumericAntd) m_Antds.elementAt(bestAntecedentsIndex)).splitPoint;
        } else {
          ((NumericAntd) m_Antds.elementAt(bestAntecedentsIndex)).supportBound =
              bestSupportBoundForAllAntecedents;
          ((NumericAntd) m_Antds.elementAt(bestAntecedentsIndex)).fuzzyYet = true;
        }

        maxPurity = maxPurityOfAllAntecedents;
      }
      finishedAntecedents[bestAntecedentsIndex] = true;
      numFinishedAntecedents++;
    }
  }