docs: public void adjustBias(List<List<IN>> develData, Function<Double,Double> evalFunction, double low, double high) {
      LineSearcher ls = new GoldenSectionLineSearch(true,1e-2,low,high);
      CRFBiasedClassifierOptimizer optimizer = new CRFBiasedClassifierOptimizer(this, evalFunction);
      double optVal = ls.minimize(optimizer);
      int bi = featureIndex.indexOf(BIAS);
      System.err.println("Class bias of "+weights[bi][0]+" reaches optimial value "+optVal);
    }