How to use

PearsonCorrelation

in

de.tudarmstadt.ukp.dkpro.statistics.correlation

/**
 * Computes the correlation between two datasets.
 * @param list1 The first dataset as a list.
 * @param list2 The second dataset as a list.
 * @return The correlation between the two datasets.
 */
public static double computeCorrelation(final List<Double> list1, final List<Double> list2)
{
  final double[] doubleArray1 = new double[list1.size()];
  final double[] doubleArray2 = new double[list2.size()];
  int off1 = 0;
  for (final double item : list1) {
    doubleArray1[off1] = item;
    off1++;
  }
  int off2 = 0;
  for (final double item : list2) {
    doubleArray2[off2] = item;
    off2++;
  }
  final double correlation = computeCorrelation(doubleArray1, doubleArray2);
  return correlation;
}

/**
 * Computes the correlation between two datasets.
 * @param list1 The first dataset as a list.
 * @param list2 The second dataset as a list.
 * @return The correlation between the two datasets.
 */
public static double computeCorrelation(List<Double> list1, List<Double> list2) {
  double[] doubleArray1 = new double[list1.size()];
  double[] doubleArray2 = new double[list2.size()];
  int off1 = 0;
  for (double item : list1) {
    doubleArray1[off1] = item;
    off1++;
  }
  int off2 = 0;
  for (double item : list2) {
    doubleArray2[off2] = item;
    off2++;
  }
  double correlation = computeCorrelation(doubleArray1, doubleArray2);
  return correlation;
}

  public static Map<String, Double> calculate(Id2Outcome id2Outcome) 
  {
    Map<String, Double> results = new HashMap<String, Double>();
    
    double[] goldstandard = id2Outcome.getGoldValues();
    double[] prediction = id2Outcome.getPredictions();
    results.put(
        PearsonCorrelation.class.getSimpleName(),
        de.tudarmstadt.ukp.dkpro.statistics.correlation.PearsonCorrelation.computeCorrelation(goldstandard, prediction)
    );
    return results; 	
  }    
}