code: @Override
    public Counter<L> logProbabilityOf(Datum<L, F> example) {
      if (platt == null) {
        throw new UnsupportedOperationException("If you want to ask for the probability, you must train a Platt model!");
      }
      Counter<L> scores = scoresOf(example);
      scores.incrementCount(null);
      Counter<L> probs = platt.logProbabilityOf(new RVFDatum<L, L>(scores));
      //System.out.println(scores+" "+probs);
      return probs;
    }
docs: Returns a counter for the log probability of each of the classes
  looking at the the sum of e^v for each count v, should be 1
  Note: Uses SloppyMath.logSum which isn't exact but isn't as
  offensively slow as doing a series of exponentials