# Package opennlp.tools.util.eval

- Interface Summary
  Interface | Description
  --- | ---
  EvaluationMonitor<T> |

- Class Summary
  Class | Description
  --- | ---
  CrossValidationPartitioner<E> | Provides access to training and test partitions for n-fold cross validation.
  CrossValidationPartitioner.TrainingSampleStream<E> | The `TrainingSampleStream` which iterates over all training elements.
  Evaluator<T> | The `Evaluator` is an abstract base class for evaluators.
  FMeasure | The `FMeasure` is an utility class for evaluators which measure precision, recall and the resulting f-measure.
  Mean | Calculates the arithmetic mean of values added with the `Mean.add(double)` method.

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