public void increment(double x, Object y) {
    KernelRegression kreg;
    double score;

    // increment all categories
    for (Object o : kernelRegressionMap.keySet()) {
      kreg = kernelRegressionMap.get(o);
      score = itemScoring.computeCategoryScore(o, y);
      kreg.increment(x, score);
    }

    // increment item
    score = itemScoring.computeItemScore(y);
    expectedScore.increment(x, score);
  }
 public double[] getPoints(Object obj) {
   KernelRegression kreg = kernelRegressionMap.get(obj);
   return kreg.getPoints();
 }
 public double[] getValues(Object obj) {
   KernelRegression kreg = kernelRegressionMap.get(obj);
   return kreg.value();
 }
 public double[] getExpectedValues() {
   return expectedScore.value();
 }