code: def keep_negative_retrain(X, y, model_generator, method_name, num_fcounts=11):
      
      return __run_measure(measures.keep_retrain, X, y, model_generator, method_name, -1, num_fcounts, __mean_pred)
docs: Keep Negative (retrain)
      xlabel = "Max fraction of features kept"
      ylabel = "Negative mean model output"
      transform = "negate"
      sort_order = 7