Example usage for weka.core Instance classValue

List of usage examples for weka.core Instance classValue

Introduction

In this page you can find the example usage for weka.core Instance classValue.

Prototype

public double classValue();

Source Link

Document

Returns an instance's class value as a floating-point number.

Usage

From source file:test.org.moa.opencl.IBk.java

License:Open Source License

/**
 * Turn the list of nearest neighbors into a probability distribution.
 *
 * @param neighbours the list of nearest neighboring instances
 * @param distances the distances of the neighbors
 * @return the probability distribution/*from w ww  . j a  v  a 2s.  c  o  m*/
 * @throws Exception if computation goes wrong or has no class attribute
 */
protected double[] makeDistribution(Instances neighbours, double[] distances) throws Exception {

    double total = 0, weight;
    double[] distribution = new double[m_NumClasses];

    // Set up a correction to the estimator
    if (m_ClassType == Attribute.NOMINAL) {
        for (int i = 0; i < m_NumClasses; i++) {
            distribution[i] = 1.0 / Math.max(1, m_Train.numInstances());
        }
        total = (double) m_NumClasses / Math.max(1, m_Train.numInstances());
    }

    for (int i = 0; i < neighbours.numInstances(); i++) {
        // Collect class counts
        Instance current = neighbours.instance(i);
        distances[i] = distances[i] * distances[i];
        distances[i] = Math.sqrt(distances[i] / m_NumAttributesUsed);
        switch (m_DistanceWeighting) {
        case WEIGHT_INVERSE:
            weight = 1.0 / (distances[i] + 0.001); // to avoid div by zero
            break;
        case WEIGHT_SIMILARITY:
            weight = 1.0 - distances[i];
            break;
        default: // WEIGHT_NONE:
            weight = 1.0;
            break;
        }
        weight *= current.weight();
        try {
            switch (m_ClassType) {
            case Attribute.NOMINAL:
                distribution[(int) current.classValue()] += weight;
                break;
            case Attribute.NUMERIC:
                distribution[0] += current.classValue() * weight;
                break;
            }
        } catch (Exception ex) {
            throw new Error("Data has no class attribute!");
        }
        total += weight;
    }

    // Normalise distribution
    if (total > 0) {
        Utils.normalize(distribution, total);
    }
    return distribution;
}

From source file:test.org.moa.opencl.IBk.java

License:Open Source License

/**
 * Select the best value for k by hold-one-out cross-validation.
 * If the class attribute is nominal, classification error is
 * minimised. If the class attribute is numeric, mean absolute
 * error is minimised/* w w  w.  ja v  a 2s  . co m*/
 */
protected void crossValidate() {

    try {
        if (m_NNSearch instanceof weka.core.neighboursearch.CoverTree)
            throw new Exception("CoverTree doesn't support hold-one-out "
                    + "cross-validation. Use some other NN " + "method.");

        double[] performanceStats = new double[m_kNNUpper];
        double[] performanceStatsSq = new double[m_kNNUpper];

        for (int i = 0; i < m_kNNUpper; i++) {
            performanceStats[i] = 0;
            performanceStatsSq[i] = 0;
        }

        m_kNN = m_kNNUpper;
        Instance instance;
        Instances neighbours;
        double[] origDistances, convertedDistances;
        for (int i = 0; i < m_Train.numInstances(); i++) {
            if (m_Debug && (i % 50 == 0)) {
                System.err.print("Cross validating " + i + "/" + m_Train.numInstances() + "\r");
            }
            instance = m_Train.instance(i);
            neighbours = m_NNSearch.kNearestNeighbours(instance, m_kNN);
            origDistances = m_NNSearch.getDistances();

            for (int j = m_kNNUpper - 1; j >= 0; j--) {
                // Update the performance stats
                convertedDistances = new double[origDistances.length];
                System.arraycopy(origDistances, 0, convertedDistances, 0, origDistances.length);
                double[] distribution = makeDistribution(neighbours, convertedDistances);
                double thisPrediction = Utils.maxIndex(distribution);
                if (m_Train.classAttribute().isNumeric()) {
                    thisPrediction = distribution[0];
                    double err = thisPrediction - instance.classValue();
                    performanceStatsSq[j] += err * err; // Squared error
                    performanceStats[j] += Math.abs(err); // Absolute error
                } else {
                    if (thisPrediction != instance.classValue()) {
                        performanceStats[j]++; // Classification error
                    }
                }
                if (j >= 1) {
                    neighbours = pruneToK(neighbours, convertedDistances, j);
                }
            }
        }

        // Display the results of the cross-validation
        for (int i = 0; i < m_kNNUpper; i++) {
            if (m_Debug) {
                System.err.print("Hold-one-out performance of " + (i + 1) + " neighbors ");
            }
            if (m_Train.classAttribute().isNumeric()) {
                if (m_Debug) {
                    if (m_MeanSquared) {
                        System.err.println(
                                "(RMSE) = " + Math.sqrt(performanceStatsSq[i] / m_Train.numInstances()));
                    } else {
                        System.err.println("(MAE) = " + performanceStats[i] / m_Train.numInstances());
                    }
                }
            } else {
                if (m_Debug) {
                    System.err.println("(%ERR) = " + 100.0 * performanceStats[i] / m_Train.numInstances());
                }
            }
        }

        // Check through the performance stats and select the best
        // k value (or the lowest k if more than one best)
        double[] searchStats = performanceStats;
        if (m_Train.classAttribute().isNumeric() && m_MeanSquared) {
            searchStats = performanceStatsSq;
        }
        double bestPerformance = Double.NaN;
        int bestK = 1;
        for (int i = 0; i < m_kNNUpper; i++) {
            if (Double.isNaN(bestPerformance) || (bestPerformance > searchStats[i])) {
                bestPerformance = searchStats[i];
                bestK = i + 1;
            }
        }
        m_kNN = bestK;
        if (m_Debug) {
            System.err.println("Selected k = " + bestK);
        }

        m_kNNValid = true;
    } catch (Exception ex) {
        throw new Error("Couldn't optimize by cross-validation: " + ex.getMessage());
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.AbstractClassifier.java

License:Open Source License

public boolean correctlyClassifies(Instance inst) {
    return Utils.maxIndex(getVotesForInstance(inst)) == (int) inst.classValue();
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.CoOzaBagASHT.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    int trueClass = (int) inst.classValue();
    for (int i = 0; i < this.ensemble.length; i++) {
        int k = MiscUtils.poisson(1.0, this.classifierRandom);
        if (k > 0) {
            Instance weightedInst = (Instance) inst.copy();
            weightedInst.setWeight(inst.weight() * k);
            if (Utils.maxIndex(this.ensemble[i].getVotesForInstance(inst)) == trueClass) { // Here we used the getVotesForInstanceFunction of HoeffdingTree
                this.error[i] += alpha * (0.0 - this.error[i]); // EWMA
            } else {
                this.error[i] += alpha * (1.0 - this.error[i]); // EWMA
            }//ww w .  jav a2  s. c  o m
            this.ensemble[i].trainOnInstance(weightedInst);
        }
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.LeveragingBag.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    int numClasses = inst.numClasses();
    //Output Codes
    if (this.initMatrixCodes == true) {
        this.matrixCodes = new int[this.ensemble.length][inst.numClasses()];
        for (int i = 0; i < this.ensemble.length; i++) {
            int numberOnes;
            int numberZeros;

            do { // until we have the same number of zeros and ones
                numberOnes = 0;/*from  w  w  w . jav a 2s .  c o m*/
                numberZeros = 0;
                for (int j = 0; j < numClasses; j++) {
                    int result = 0;
                    if (j == 1 && numClasses == 2) {
                        result = 1 - this.matrixCodes[i][0];
                    } else {
                        result = (this.classifierRandom.nextBoolean() ? 1 : 0);
                    }
                    this.matrixCodes[i][j] = result;
                    if (result == 1)
                        numberOnes++;
                    else
                        numberZeros++;
                }
            } while ((numberOnes - numberZeros) * (numberOnes - numberZeros) > (this.ensemble.length % 2));

        }
        this.initMatrixCodes = false;
    }

    boolean Change = false;
    double w = 1.0;
    double mt = 0.0;
    Instance weightedInst = (Instance) inst.copy();
    /*for (int i = 0; i < this.ensemble.length; i++) {
      if (this.outputCodesOption.isSet()) {
          weightedInst.setClassValue((double) this.matrixCodes[i][(int) inst.classValue()] );
      }
      if(!this.ensemble[i].correctlyClassifies(weightedInst)) {
          mt++;
      }
      }*/
    //update w
    w = this.weightShrinkOption.getValue(); //1.0 +mt/2.0;
    //Train ensemble of classifiers
    for (int i = 0; i < this.ensemble.length; i++) {
        int k = MiscUtils.poisson(w, this.classifierRandom);
        if (k > 0) {
            if (this.outputCodesOption.isSet()) {
                weightedInst.setClassValue((double) this.matrixCodes[i][(int) inst.classValue()]);
            }
            weightedInst.setWeight(inst.weight() * k);
            this.ensemble[i].trainOnInstance(weightedInst);
        }
        boolean correctlyClassifies = this.ensemble[i].correctlyClassifies(weightedInst);
        double ErrEstim = this.ADError[i].getEstimation();
        if (this.ADError[i].setInput(correctlyClassifies ? 0 : 1))
            if (this.ADError[i].getEstimation() > ErrEstim)
                Change = true;
    }
    if (Change) {
        numberOfChangesDetected++;
        double max = 0.0;
        int imax = -1;
        for (int i = 0; i < this.ensemble.length; i++) {
            if (max < this.ADError[i].getEstimation()) {
                max = this.ADError[i].getEstimation();
                imax = i;
            }
        }
        if (imax != -1) {
            this.ensemble[imax].resetLearning();
            //this.ensemble[imax].trainOnInstance(inst);
            this.ADError[imax] = new ADWIN((double) this.deltaAdwinOption.getValue());
        }
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.LeveragingBagHalf.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    int numClasses = inst.numClasses();
    //Output Codes
    if (this.initMatrixCodes == true) {
        this.matrixCodes = new int[this.ensemble.length][inst.numClasses()];
        for (int i = 0; i < this.ensemble.length; i++) {
            int numberOnes;
            int numberZeros;

            do { // until we have the same number of zeros and ones
                numberOnes = 0;//from w  ww.  j  a  v a2  s .  c  om
                numberZeros = 0;
                for (int j = 0; j < numClasses; j++) {
                    int result = 0;
                    if (j == 1 && numClasses == 2) {
                        result = 1 - this.matrixCodes[i][0];
                    } else {
                        result = (this.classifierRandom.nextBoolean() ? 1 : 0);
                    }
                    this.matrixCodes[i][j] = result;
                    if (result == 1)
                        numberOnes++;
                    else
                        numberZeros++;
                }
            } while ((numberOnes - numberZeros) * (numberOnes - numberZeros) > (this.ensemble.length % 2));

        }
        this.initMatrixCodes = false;
    }

    boolean Change = false;
    double w = 1.0;
    double mt = 0.0;
    Instance weightedInst = (Instance) inst.copy();
    //Train ensemble of classifiers
    for (int i = 0; i < this.ensemble.length; i++) {
        int k = this.classifierRandom.nextBoolean() ? 0 : (int) this.weightShrinkOption.getValue(); //half bagging
        if (k > 0) {
            if (this.outputCodesOption.isSet()) {
                weightedInst.setClassValue((double) this.matrixCodes[i][(int) inst.classValue()]);
            }
            weightedInst.setWeight(k);
            this.ensemble[i].trainOnInstance(weightedInst);
        }
        boolean correctlyClassifies = this.ensemble[i].correctlyClassifies(weightedInst);
        double ErrEstim = this.ADError[i].getEstimation();
        if (this.ADError[i].setInput(correctlyClassifies ? 0 : 1))
            if (this.ADError[i].getEstimation() > ErrEstim)
                Change = true;
    }
    if (Change) {
        numberOfChangesDetected++;
        double max = 0.0;
        int imax = -1;
        for (int i = 0; i < this.ensemble.length; i++) {
            if (max < this.ADError[i].getEstimation()) {
                max = this.ADError[i].getEstimation();
                imax = i;
            }
        }
        if (imax != -1) {
            this.ensemble[imax].resetLearning();
            //this.ensemble[imax].trainOnInstance(inst);
            this.ADError[imax] = new ADWIN((double) this.deltaAdwinOption.getValue());
        }
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.LeveragingBagWT.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    int numClasses = inst.numClasses();
    //Output Codes
    if (this.initMatrixCodes == true) {
        this.matrixCodes = new int[this.ensemble.length][inst.numClasses()];
        for (int i = 0; i < this.ensemble.length; i++) {
            int numberOnes;
            int numberZeros;

            do { // until we have the same number of zeros and ones
                numberOnes = 0;/*w w w . ja va 2 s.co m*/
                numberZeros = 0;
                for (int j = 0; j < numClasses; j++) {
                    int result = 0;
                    if (j == 1 && numClasses == 2) {
                        result = 1 - this.matrixCodes[i][0];
                    } else {
                        result = (this.classifierRandom.nextBoolean() ? 1 : 0);
                    }
                    this.matrixCodes[i][j] = result;
                    if (result == 1)
                        numberOnes++;
                    else
                        numberZeros++;
                }
            } while ((numberOnes - numberZeros) * (numberOnes - numberZeros) > (this.ensemble.length % 2));

        }
        this.initMatrixCodes = false;
    }

    boolean Change = false;
    double w = 1.0;
    double mt = 0.0;
    Instance weightedInst = (Instance) inst.copy();
    //update w
    w = this.weightShrinkOption.getValue();
    //Train ensemble of classifiers
    for (int i = 0; i < this.ensemble.length; i++) {
        int k = 1 + MiscUtils.poisson(w, this.classifierRandom);
        if (k > 0) {
            if (this.outputCodesOption.isSet()) {
                weightedInst.setClassValue((double) this.matrixCodes[i][(int) inst.classValue()]);
            }
            weightedInst.setWeight(inst.weight() * k);
            this.ensemble[i].trainOnInstance(weightedInst);
        }
        boolean correctlyClassifies = this.ensemble[i].correctlyClassifies(weightedInst);
        double ErrEstim = this.ADError[i].getEstimation();
        if (this.ADError[i].setInput(correctlyClassifies ? 0 : 1))
            if (this.ADError[i].getEstimation() > ErrEstim)
                Change = true;
    }
    if (Change) {
        numberOfChangesDetected++;
        double max = 0.0;
        int imax = -1;
        for (int i = 0; i < this.ensemble.length; i++) {
            if (max < this.ADError[i].getEstimation()) {
                max = this.ADError[i].getEstimation();
                imax = i;
            }
        }
        if (imax != -1) {
            this.ensemble[imax].resetLearning();
            //this.ensemble[imax].trainOnInstance(inst);
            this.ADError[imax] = new ADWIN((double) this.deltaAdwinOption.getValue());
        }
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.LeveragingSubag.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    int numClasses = inst.numClasses();
    //Output Codes
    if (this.initMatrixCodes == true) {
        this.matrixCodes = new int[this.ensemble.length][inst.numClasses()];
        for (int i = 0; i < this.ensemble.length; i++) {
            int numberOnes;
            int numberZeros;

            do { // until we have the same number of zeros and ones
                numberOnes = 0;//  w  w  w.j a  v  a 2  s .  c om
                numberZeros = 0;
                for (int j = 0; j < numClasses; j++) {
                    int result = 0;
                    if (j == 1 && numClasses == 2) {
                        result = 1 - this.matrixCodes[i][0];
                    } else {
                        result = (this.classifierRandom.nextBoolean() ? 1 : 0);
                    }
                    this.matrixCodes[i][j] = result;
                    if (result == 1)
                        numberOnes++;
                    else
                        numberZeros++;
                }
            } while ((numberOnes - numberZeros) * (numberOnes - numberZeros) > (this.ensemble.length % 2));

        }
        this.initMatrixCodes = false;
    }

    boolean Change = false;
    double w = 1.0;
    double mt = 0.0;
    Instance weightedInst = (Instance) inst.copy();

    //Train ensemble of classifiers
    for (int i = 0; i < this.ensemble.length; i++) {
        int k = MiscUtils.poisson(1, this.classifierRandom);
        k = (k > 0) ? (int) this.weightShrinkOption.getValue() : 0;
        if (k > 0) {
            if (this.outputCodesOption.isSet()) {
                weightedInst.setClassValue((double) this.matrixCodes[i][(int) inst.classValue()]);
            }
            weightedInst.setWeight(k);
            this.ensemble[i].trainOnInstance(weightedInst);
        }
        boolean correctlyClassifies = this.ensemble[i].correctlyClassifies(weightedInst);
        double ErrEstim = this.ADError[i].getEstimation();
        if (this.ADError[i].setInput(correctlyClassifies ? 0 : 1))
            if (this.ADError[i].getEstimation() > ErrEstim)
                Change = true;
    }
    if (Change) {
        numberOfChangesDetected++;
        double max = 0.0;
        int imax = -1;
        for (int i = 0; i < this.ensemble.length; i++) {
            if (max < this.ADError[i].getEstimation()) {
                max = this.ADError[i].getEstimation();
                imax = i;
            }
        }
        if (imax != -1) {
            this.ensemble[imax].resetLearning();
            this.ADError[imax] = new ADWIN((double) this.deltaAdwinOption.getValue());
        }
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.OzaBagASHOT.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    final int trueClass = (int) inst.classValue();
    //System.out.println("Ensemble Length " + this.ensemble.length);
    for (int i = 0; i < this.ensemble.length; i++) {
        final int k = MiscUtils.poisson(1.0, this.classifierRandom);
        if (k > 0) {
            final Instance weightedInst = (Instance) inst.copy();
            weightedInst.setWeight(inst.weight() * k);
            if (Utils.maxIndex(this.ensemble[i].getVotesForInstance(inst)) == trueClass) {
                this.error[i] += alpha * (0.0 - this.error[i]); //EWMA
            } else {
                this.error[i] += alpha * (1.0 - this.error[i]); //EWMA
            }/* ww  w  .j a  v a  2 s  . c o  m*/
            this.ensemble[i].trainOnInstance(weightedInst);
        }
        //   System.out.println("ClassifierRandom: " + k);
        //System.out.println("EWMA Error Ensemble "+i+" "+ this.error[i]);
        if (this.error[i] > 0.6) {
            System.out.println("Error is " + this.error[i]);
            System.out.println("Ensemble " + i);
            System.err.println("Warning!!!!!");
        }
    }
}

From source file:tr.gov.ulakbim.jDenetX.classifiers.OzaBoostAdwin.java

License:Open Source License

@Override
public void trainOnInstanceImpl(Instance inst) {
    int numClasses = inst.numClasses();
    // Set log (k-1) and (k-1) for SAMME Method
    if (this.sammeOption.isSet()) {
        this.Km1 = numClasses - 1;
        this.logKm1 = Math.log(this.Km1);
        this.initKm1 = false;
    }/*from   w w w .ja va2s. c o m*/
    //Output Codes
    if (this.initMatrixCodes) {

        this.matrixCodes = new int[this.ensemble.length][inst.numClasses()];
        for (int i = 0; i < this.ensemble.length; i++) {
            int numberOnes;
            int numberZeros;

            do { // until we have the same number of zeros and ones
                numberOnes = 0;
                numberZeros = 0;
                for (int j = 0; j < numClasses; j++) {
                    int result = 0;
                    if (j == 1 && numClasses == 2) {
                        result = 1 - this.matrixCodes[i][0];
                    } else {
                        result = (this.classifierRandom.nextBoolean() ? 1 : 0);
                    }
                    this.matrixCodes[i][j] = result;
                    if (result == 1)
                        numberOnes++;
                    else
                        numberZeros++;
                }
            } while ((numberOnes - numberZeros) * (numberOnes - numberZeros) > (this.ensemble.length % 2));

        }
        this.initMatrixCodes = false;
    }

    boolean Change = false;
    double lambda_d = 1.0;
    Instance weightedInst = (Instance) inst.copy();
    for (int i = 0; i < this.ensemble.length; i++) {
        double k = this.pureBoostOption.isSet() ? lambda_d
                : MiscUtils.poisson(lambda_d * this.Km1, this.classifierRandom);
        if (k > 0.0) {
            if (this.outputCodesOption.isSet()) {
                weightedInst.setClassValue((double) this.matrixCodes[i][(int) inst.classValue()]);
            }
            weightedInst.setWeight(inst.weight() * k);
            this.ensemble[i].trainOnInstance(weightedInst);
        }
        boolean correctlyClassifies = this.ensemble[i].correctlyClassifies(weightedInst);
        if (correctlyClassifies) {
            this.scms[i] += lambda_d;
            lambda_d *= this.trainingWeightSeenByModel / (2 * this.scms[i]);
        } else {
            this.swms[i] += lambda_d;
            lambda_d *= this.trainingWeightSeenByModel / (2 * this.swms[i]);
        }

        double ErrEstim = this.ADError[i].getEstimation();
        if (this.ADError[i].setInput(correctlyClassifies ? 0 : 1))
            if (this.ADError[i].getEstimation() > ErrEstim)
                Change = true;
    }
    if (Change) {
        numberOfChangesDetected++;
        double max = 0.0;
        int imax = -1;
        for (int i = 0; i < this.ensemble.length; i++) {
            if (max < this.ADError[i].getEstimation()) {
                max = this.ADError[i].getEstimation();
                imax = i;
            }
        }
        if (imax != -1) {
            this.ensemble[imax].resetLearning();
            //this.ensemble[imax].trainOnInstance(inst);
            this.ADError[imax] = new ADWIN((double) this.deltaAdwinOption.getValue());
            this.scms[imax] = 0;
            this.swms[imax] = 0;
        }
    }
}