code: public ClassificationMetrics validate(Dataframe testDataset) {
          logger.info("validate()");
  
          predict(testDataset);
  
          ClassificationMetrics vm = new ClassificationMetrics(testDataset);
  
          return vm;
      }
docs: It validates the modeler using the provided dataset and it returns the ClassificationMetrics. The testDataset should contain the real target variables.
  
  @param testDataset
  @return