Package weka.classifiers

# Class Evaluation

java.lang.Object
weka.classifiers.Evaluation

All Implemented Interfaces:
  `Serializable`, `RevisionHandler`, `Summarizable`

Direct Known Subclasses:
  `AggregateableEvaluation`

public class Evaluation extends Object implements Serializable, Summarizable, RevisionHandler
Class for evaluating machine learning models. Delegates to the actual implementation in weka.classifiers.evaluation.Evaluation.

-------------------------------------------------------------------

General options when evaluating a learning scheme from the command-line:

-t filename
Name of the file with the training data. (required)

-T filename
Name of the file with the test data. If missing a cross-validation is performed.

-c index
Index of the class attribute (1, 2, ...; default: last).

-x number
The number of folds for the cross-validation (default: 10).

-no-cv
No cross validation. If no test file is provided, no evaluation is done.

-split-percentage percentage
Sets the percentage for the train/test set split, e.g., 66.

-preserve-order
Preserves the order in the percentage split instead of randomizing the data first with the seed value ('-s').

-s seed
Random number seed for the cross-validation and percentage split (default: 1).

-m filename
The name of a file containing a cost matrix.

-l filename
Loads classifier from the given file. In case the filename ends with ".xml", a PMML file is loaded or, if that fails, options are loaded from XML.

-d filename
Saves classifier built from the training data into the given file. In case the filename ends with ".xml" the options are saved XML, not the model.

-v
Outputs no statistics for the training data.

-o
Outputs statistics only, not the classifier.

-i
Outputs information-retrieval statistics per class.

-k
Outputs information-theoretic statistics.

-classifications "weka.classifiers.evaluation.output.prediction.AbstractOutput + options"
Uses the specified class for generating the classification output. E.g.: weka.classifiers.evaluation.output.prediction.PlainText or : weka.classifiers.evaluation.output.prediction.CSV -p range
Outputs predictions for test instances (or the train instances if no test instances provided and -no-cv is used), along with the attributes in the specified range (and nothing else). Use '-p 0' if no attributes are desired.

Deprecated: use "-classifications ..." instead.

-distribution
Outputs the distribution instead of only the prediction in conjunction with the '-p' option (only nominal classes).

Deprecated: use "-classifications ..." instead.

-no-predictions
Turns off the collection of predictions in order to conserve memory.

-r
Outputs cumulative margin distribution (and nothing else).

-g
Only for classifiers that implement "Graphable." Outputs the graph representation of the classifier (and nothing else).

-xml filename | xml-string
Retrieves the options from the XML-data instead of the command line.

-threshold-file file
The file to save the threshold data to. The format is determined by the extensions, e.g., '.arff' for ARFF format or '.csv' for CSV.

-threshold-label label
The class label to determine the threshold data for (default is the first label)

-------------------------------------------------------------------

Example usage as the main of a classifier (called FunkyClassifier): `

     public static void main(String [] args) {
       runClassifier(new FunkyClassifier(), args);
     }

`

------------------------------------------------------------------

Example usage from within an application: `

     Instances trainInstances = ... instances got from somewhere
     Instances testInstances = ... instances got from somewhere
     Classifier scheme = ... scheme got from somewhere

     Evaluation evaluation = new Evaluation(trainInstances);
     evaluation.evaluateModel(scheme, testInstances);
     System.out.println(evaluation.toSummaryString());

`

Version:
  $Revision: 14450 $
Author:
  Eibe Frank (eibe@cs.waikato.ac.nz), Len Trigg (trigg@cs.waikato.ac.nz)
See Also:
  - Serialized Form

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final String[]`
  `BUILT_IN_EVAL_METRICS`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Evaluation(Instances data)`
  `Evaluation(Instances data, CostMatrix costMatrix)`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `double`
  `areaUnderPRC(int classIndex)`
  Returns the area under precision-recall curve (AUPRC) for those predictions that have been collected in the evaluateClassifier(Classifier, Instances) method.
  `double`
  `areaUnderROC(int classIndex)`
  Returns the area under ROC for those predictions that have been collected in the evaluateClassifier(Classifier, Instances) method.
  `final double`
  `avgCost()`
  Gets the average cost, that is, total cost of misclassifications (incorrect plus unclassified) over the total number of instances.
  `double[][]`
  `confusionMatrix()`
  Returns a copy of the confusion matrix.
  `final double`
  `correct()`
  Gets the number of instances correctly classified (that is, for which a correct prediction was made).
  `final double`
  `correlationCoefficient()`
  Returns the correlation coefficient if the class is numeric.
  `final double`
  `coverageOfTestCasesByPredictedRegions()`
  Gets the coverage of the test cases by the predicted regions at the confidence level specified when evaluation was performed.
  `void`
  `crossValidateModel(String classifierString, Instances data, int numFolds, String[] options, Random random)`
  Performs a (stratified if class is nominal) cross-validation for a classifier on a set of instances.
  `void`
  `crossValidateModel(Classifier classifier, Instances data, int numFolds, Random random)`
  Performs a (stratified if class is nominal) cross-validation for a classifier on a set of instances.
  `void`
  `crossValidateModel(Classifier classifier, Instances data, int numFolds, Random random, Object... forPredictionsPrinting)`
  Performs a (stratified if class is nominal) cross-validation for a classifier on a set of instances.
  `boolean`
  `equals(Object obj)`
  Tests whether the current evaluation object is equal to another evaluation object.
  `final double`
  `errorRate()`
  Returns the estimated error rate or the root mean squared error (if the class is numeric).
  `static String`
  `evaluateModel(String classifierString, String[] options)`
  Evaluates a classifier with the options given in an array of strings.
  `static String`
  `evaluateModel(Classifier classifier, String[] options)`
  Evaluates a classifier with the options given in an array of strings.
  `double[]`
  `evaluateModel(Classifier classifier, Instances data, Object... forPredictionsPrinting)`
  Evaluates the classifier on a given set of instances.
  `double`
  `evaluateModelOnce(double[] dist, Instance instance)`
  Evaluates the supplied distribution on a single instance.
  `void`
  `evaluateModelOnce(double prediction, Instance instance)`
  Evaluates the supplied prediction on a single instance.
  `double`
  `evaluateModelOnce(Classifier classifier, Instance instance)`
  Evaluates the classifier on a single instance.
  `double`
  `evaluateModelOnceAndRecordPrediction(double[] dist, Instance instance)`
  Evaluates the supplied distribution on a single instance.
  `double`
  `evaluateModelOnceAndRecordPrediction(Classifier classifier, Instance instance)`
  Evaluates the classifier on a single instance and records the prediction.
  `double`
  `evaluationForSingleInstance(double[] dist, Instance instance, boolean storePredictions)`
  Evaluates the supplied distribution on a single instance.
  `double`
  `falseNegativeRate(int classIndex)`
  Calculate the false negative rate with respect to a particular class.
  `double`
  `falsePositiveRate(int classIndex)`
  Calculate the false positive rate with respect to a particular class.
  `double`
  `fMeasure(int classIndex)`
  Calculate the F-Measure with respect to a particular class.
  `static List<String>`
  `getAllEvaluationMetricNames()`
  Utility method to get a list of the names of all built-in and plugin evaluation metrics
  `double[]`
  `getClassPriors()`
  Get the current weighted class counts.
  `boolean`
  `getDiscardPredictions()`
  Returns whether predictions are not recorded at all, in order to conserve memory.
  `Instances`
  `getHeader()`
  Returns the header of the underlying dataset.
  `List<String>`
  `getMetricsToDisplay()`
  Get a list of the names of metrics to have appear in the output The default is to display all built in metrics and plugin metrics that haven't been globally disabled.
  `AbstractEvaluationMetric`
  `getPluginMetric(String name)`
  Get the named plugin evaluation metric
  `List<AbstractEvaluationMetric>`
  `getPluginMetrics()`
  Returns the list of plugin metrics in use (or null if there are none)
  `String`
  `getRevision()`
  Returns the revision string.
  `final double`
  `incorrect()`
  Gets the number of instances incorrectly classified (that is, for which an incorrect prediction was made).
  `final double`
  `kappa()`
  Returns value of kappa statistic if class is nominal.
  `final double`
  `KBInformation()`
  Return the total Kononenko & Bratko Information score in bits.
  `final double`
  `KBMeanInformation()`
  Return the Kononenko & Bratko Information score in bits per instance.
  `final double`
  `KBRelativeInformation()`
  Return the Kononenko & Bratko Relative Information score.
  `static void`
  `main(String[] args)`
  A test method for this class.
  `double`
  `matthewsCorrelationCoefficient(int classIndex)`
  Calculates the matthews correlation coefficient (sometimes called phi coefficient) for the supplied class
  `final double`
  `meanAbsoluteError()`
  Returns the mean absolute error.
  `final double`
  `meanPriorAbsoluteError()`
  Returns the mean absolute error of the prior.
  `double`
  `numFalseNegatives(int classIndex)`
  Calculate number of false negatives with respect to a particular class.
  `double`
  `numFalsePositives(int classIndex)`
  Calculate number of false positives with respect to a particular class.
  `final double`
  `numInstances()`
  Gets the number of test instances that had a known class value (actually the sum of the weights of test instances with known class value).
  `double`
  `numTrueNegatives(int classIndex)`
  Calculate the number of true negatives with respect to a particular class.
  `double`
  `numTruePositives(int classIndex)`
  Calculate the number of true positives with respect to a particular class.
  `final double`
  `pctCorrect()`
  Gets the percentage of instances correctly classified (that is, for which a correct prediction was made).
  `final double`
  `pctIncorrect()`
  Gets the percentage of instances incorrectly classified (that is, for which an incorrect prediction was made).
  `final double`
  `pctUnclassified()`
  Gets the percentage of instances not classified (that is, for which no prediction was made by the classifier).
  `double`
  `precision(int classIndex)`
  Calculate the precision with respect to a particular class.
  `ArrayList<Prediction>`
  `predictions()`
  Returns the predictions that have been collected.
  `final double`
  `priorEntropy()`
  Calculate the entropy of the prior distribution.
  `double`
  `recall(int classIndex)`
  Calculate the recall with respect to a particular class.
  `final double`
  `relativeAbsoluteError()`
  Returns the relative absolute error.
  `final double`
  `rootMeanPriorSquaredError()`
  Returns the root mean prior squared error.
  `final double`
  `rootMeanSquaredError()`
  Returns the root mean squared error.
  `final double`
  `rootRelativeSquaredError()`
  Returns the root relative squared error if the class is numeric.
  `void`
  `setDiscardPredictions(boolean value)`
  Sets whether to discard predictions, ie, not storing them for future reference via predictions() method in order to conserve memory.
  `void`
  `setMetricsToDisplay(List<String> display)`
  Set a list of the names of metrics to have appear in the output.
  `void`
  `setPriors(Instances train)`
  Sets the class prior probabilities.
  `final double`
  `SFEntropyGain()`
  Returns the total SF, which is the null model entropy minus the scheme entropy.
  `final double`
  `SFMeanEntropyGain()`
  Returns the SF per instance, which is the null model entropy minus the scheme entropy, per instance.
  `final double`
  `SFMeanPriorEntropy()`
  Returns the entropy per instance for the null model.
  `final double`
  `SFMeanSchemeEntropy()`
  Returns the entropy per instance for the scheme.
  `final double`
  `SFPriorEntropy()`
  Returns the total entropy for the null model.
  `final double`
  `SFSchemeEntropy()`
  Returns the total entropy for the scheme.
  `final double`
  `sizeOfPredictedRegions()`
  Gets the average size of the predicted regions, relative to the range of the target in the training data, at the confidence level specified when evaluation was performed.
  `String`
  `toClassDetailsString()`
  Generates a breakdown of the accuracy for each class (with default title), incorporating various information-retrieval statistics, such as true/false positive rate, precision/recall/F-Measure.
  `String`
  `toClassDetailsString(String title)`
  Generates a breakdown of the accuracy for each class, incorporating various information-retrieval statistics, such as true/false positive rate, precision/recall/F-Measure.
  `String`
  `toCumulativeMarginDistributionString()`
  Output the cumulative margin distribution as a string suitable for input for gnuplot or similar package.
  `void`
  `toggleEvalMetrics(List<String> metricsToToggle)`
  Toggle the output of the metrics specified in the supplied list.
  `String`
  `toMatrixString()`
  Calls toMatrixString() with a default title.
  `String`
  `toMatrixString(String title)`
  Outputs the performance statistics as a classification confusion matrix.
  `String`
  `toSummaryString()`
  Calls toSummaryString() with no title and no complexity stats.
  `String`
  `toSummaryString(boolean printComplexityStatistics)`
  Calls toSummaryString() with a default title.
  `String`
  `toSummaryString(String title, boolean printComplexityStatistics)`
  Outputs the performance statistics in summary form.
  `final double`
  `totalCost()`
  Gets the total cost, that is, the cost of each prediction times the weight of the instance, summed over all instances.
  `double`
  `trueNegativeRate(int classIndex)`
  Calculate the true negative rate with respect to a particular class.
  `double`
  `truePositiveRate(int classIndex)`
  Calculate the true positive rate with respect to a particular class.
  `final double`
  `unclassified()`
  Gets the number of instances not classified (that is, for which no prediction was made by the classifier).
  `double`
  `unweightedMacroFmeasure()`
  Unweighted macro-averaged F-measure.
  `double`
  `unweightedMicroFmeasure()`
  Unweighted micro-averaged F-measure.
  `void`
  `updatePriors(Instance instance)`
  Updates the class prior probabilities or the mean respectively (when incrementally training).
  `void`
  `useNoPriors()`
  disables the use of priors, e.g., in case of de-serialized schemes that have no access to the original training set, but are evaluated on a set set.
  `double`
  `weightedAreaUnderPRC()`
  Calculates the weighted (by class size) AUPRC.
  `double`
  `weightedAreaUnderROC()`
  Calculates the weighted (by class size) AUC.
  `double`
  `weightedFalseNegativeRate()`
  Calculates the weighted (by class size) false negative rate.
  `double`
  `weightedFalsePositiveRate()`
  Calculates the weighted (by class size) false positive rate.
  `double`
  `weightedFMeasure()`
  Calculates the macro weighted (by class size) average F-Measure.
  `double`
  `weightedMatthewsCorrelation()`
  Calculates the weighted (by class size) matthews correlation coefficient.
  `double`
  `weightedPrecision()`
  Calculates the weighted (by class size) precision.
  `double`
  `weightedRecall()`
  Calculates the weighted (by class size) recall.
  `double`
  `weightedTrueNegativeRate()`
  Calculates the weighted (by class size) true negative rate.
  `double`
  `weightedTruePositiveRate()`
  Calculates the weighted (by class size) true positive rate.
  `static String`
  `wekaStaticWrapper(Sourcable classifier, String className)`
  Wraps a static classifier in enough source to test using the weka class libraries.

  ### Methods inherited from class java.lang.Object

  `getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Field Details

  - ### BUILT_IN_EVAL_METRICS

    public static final String[] BUILT_IN_EVAL_METRICS

- ## Constructor Details

  - ### Evaluation

    public Evaluation(Instances data) throws Exception
    Throws:
      `Exception`

  - ### Evaluation

    public Evaluation(Instances data, CostMatrix costMatrix) throws Exception
    Throws:
      `Exception`

- ## Method Details

  - ### getAllEvaluationMetricNames

    public static List<String> getAllEvaluationMetricNames()
    Utility method to get a list of the names of all built-in and plugin evaluation metrics
    Returns:
      the complete list of available evaluation metrics

  - ### getHeader

    public Instances getHeader()
    Returns the header of the underlying dataset.
    Returns:
      the header information

  - ### getPluginMetrics

    public List<AbstractEvaluationMetric> getPluginMetrics()
    Returns the list of plugin metrics in use (or null if there are none)
    Returns:
      the list of plugin metrics

  - ### getPluginMetric

    public AbstractEvaluationMetric getPluginMetric(String name)
    Get the named plugin evaluation metric
    Parameters:
      `name` - the name of the metric (as returned by AbstractEvaluationMetric.getName()) or the fully qualified class name of the metric to find
    Returns:
      the metric or null if the metric is not in the list of plugin metrics

  - ### setMetricsToDisplay

    public void setMetricsToDisplay(List<String> display)
    Set a list of the names of metrics to have appear in the output. The default is to display all built in metrics and plugin metrics that haven't been globally disabled.
    Parameters:
      `display` - a list of metric names to have appear in the output

  - ### getMetricsToDisplay

    public List<String> getMetricsToDisplay()
    Get a list of the names of metrics to have appear in the output The default is to display all built in metrics and plugin metrics that haven't been globally disabled.
    Returns:
      a list of metric names to have appear in the output

  - ### toggleEvalMetrics

    public void toggleEvalMetrics(List<String> metricsToToggle)
    Toggle the output of the metrics specified in the supplied list.
    Parameters:
      `metricsToToggle` - a list of metrics to toggle

  - ### setDiscardPredictions

    public void setDiscardPredictions(boolean value)
    Sets whether to discard predictions, ie, not storing them for future reference via predictions() method in order to conserve memory.
    Parameters:
      `value` - true if to discard the predictions
    See Also:
      - `predictions()`

  - ### getDiscardPredictions

    public boolean getDiscardPredictions()
    Returns whether predictions are not recorded at all, in order to conserve memory.
    Returns:
      true if predictions are not recorded
    See Also:
      - `predictions()`

  - ### areaUnderROC

    public double areaUnderROC(int classIndex)
    Returns the area under ROC for those predictions that have been collected in the evaluateClassifier(Classifier, Instances) method. Returns Utils.missingValue() if the area is not available.
    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the area under the ROC curve or not a number

  - ### weightedAreaUnderROC

    public double weightedAreaUnderROC()
    Calculates the weighted (by class size) AUC.
    Returns:
      the weighted AUC.

  - ### areaUnderPRC

    public double areaUnderPRC(int classIndex)
    Returns the area under precision-recall curve (AUPRC) for those predictions that have been collected in the evaluateClassifier(Classifier, Instances) method. Returns Utils.missingValue() if the area is not available.
    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the area under the precision-recall curve or not a number

  - ### weightedAreaUnderPRC

    public double weightedAreaUnderPRC()
    Calculates the weighted (by class size) AUPRC.
    Returns:
      the weighted AUPRC.

  - ### confusionMatrix

    public double[][] confusionMatrix()
    Returns a copy of the confusion matrix.
    Returns:
      a copy of the confusion matrix as a two-dimensional array

  - ### crossValidateModel

    public void crossValidateModel(Classifier classifier, Instances data, int numFolds, Random random) throws Exception
    Performs a (stratified if class is nominal) cross-validation for a classifier on a set of instances. Now performs a deep copy of the classifier before each call to buildClassifier() (just in case the classifier is not initialized properly).
    Parameters:
      `classifier` - the classifier with any options set.
      `data` - the data on which the cross-validation is to be performed
      `numFolds` - the number of folds for the cross-validation
      `random` - random number generator for randomization
    Throws:
      `Exception` - if a classifier could not be generated successfully or the class is not defined

  - ### crossValidateModel

    public void crossValidateModel(Classifier classifier, Instances data, int numFolds, Random random, Object... forPredictionsPrinting) throws Exception
    Performs a (stratified if class is nominal) cross-validation for a classifier on a set of instances. Now performs a deep copy of the classifier before each call to buildClassifier() (just in case the classifier is not initialized properly).
    Parameters:
      `classifier` - the classifier with any options set.
      `data` - the data on which the cross-validation is to be performed
      `numFolds` - the number of folds for the cross-validation
      `random` - random number generator for randomization
      `forPredictionsPrinting` - varargs parameter that, if supplied, is expected to hold a weka.classifiers.evaluation.output.prediction.AbstractOutput object
    Throws:
      `Exception` - if a classifier could not be generated successfully or the class is not defined

  - ### crossValidateModel

    public void crossValidateModel(String classifierString, Instances data, int numFolds, String[] options, Random random) throws Exception
    Performs a (stratified if class is nominal) cross-validation for a classifier on a set of instances.
    Parameters:
      `classifierString` - a string naming the class of the classifier
      `data` - the data on which the cross-validation is to be performed
      `numFolds` - the number of folds for the cross-validation
      `options` - the options to the classifier. Any options
      `random` - the random number generator for randomizing the data accepted by the classifier will be removed from this array.
    Throws:
      `Exception` - if a classifier could not be generated successfully or the class is not defined

  - ### evaluateModel

    public static String evaluateModel(String classifierString, String[] options) throws Exception
    Evaluates a classifier with the options given in an array of strings.

    Valid options are:

    -t filename
    Name of the file with the training data. (required)

    -T filename
    Name of the file with the test data. If missing a cross-validation is performed.

    -c index
    Index of the class attribute (1, 2, ...; default: last).

    -x number
    The number of folds for the cross-validation (default: 10).

    -no-cv
    No cross validation. If no test file is provided, no evaluation is done.

    -split-percentage percentage
    Sets the percentage for the train/test set split, e.g., 66.

    -preserve-order
    Preserves the order in the percentage split instead of randomizing the data first with the seed value ('-s').

    -s seed
    Random number seed for the cross-validation and percentage split (default: 1).

    -m filename
    The name of a file containing a cost matrix.

    -l filename
    Loads classifier from the given file. In case the filename ends with ".xml",a PMML file is loaded or, if that fails, options are loaded from XML.

    -d filename
    Saves classifier built from the training data into the given file. In case the filename ends with ".xml" the options are saved XML, not the model.

    -v
    Outputs no statistics for the training data.

    -o
    Outputs statistics only, not the classifier.

    -i
    Outputs detailed information-retrieval statistics per class.

    -k
    Outputs information-theoretic statistics.

    -classifications "weka.classifiers.evaluation.output.prediction.AbstractOutput + options"
    Uses the specified class for generating the classification output. E.g.: weka.classifiers.evaluation.output.prediction.PlainText or : weka.classifiers.evaluation.output.prediction.CSV -p range
    Outputs predictions for test instances (or the train instances if no test instances provided and -no-cv is used), along with the attributes in the specified range (and nothing else). Use '-p 0' if no attributes are desired.

    Deprecated: use "-classifications ..." instead.

    -distribution
    Outputs the distribution instead of only the prediction in conjunction with the '-p' option (only nominal classes).

    Deprecated: use "-classifications ..." instead.

    -no-predictions
    Turns off the collection of predictions in order to conserve memory.

    -r
    Outputs cumulative margin distribution (and nothing else).

    -g
    Only for classifiers that implement "Graphable." Outputs the graph representation of the classifier (and nothing else).

    -xml filename | xml-string
    Retrieves the options from the XML-data instead of the command line.

    -threshold-file file
    The file to save the threshold data to. The format is determined by the extensions, e.g., '.arff' for ARFF format or '.csv' for CSV.

    -threshold-label label
    The class label to determine the threshold data for (default is the first label)

    Parameters:
      `classifierString` - class of machine learning classifier as a string
      `options` - the array of string containing the options
    Returns:
      a string describing the results
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### evaluateModel

    public static String evaluateModel(Classifier classifier, String[] options) throws Exception
    Evaluates a classifier with the options given in an array of strings.

    Valid options are:

    -t name of training file
    Name of the file with the training data. (required)

    -T name of test file
    Name of the file with the test data. If missing a cross-validation is performed.

    -c class index
    Index of the class attribute (1, 2, ...; default: last).

    -x number of folds
    The number of folds for the cross-validation (default: 10).

    -no-cv
    No cross validation. If no test file is provided, no evaluation is done.

    -split-percentage percentage
    Sets the percentage for the train/test set split, e.g., 66.

    -preserve-order
    Preserves the order in the percentage split instead of randomizing the data first with the seed value ('-s').

    -s seed
    Random number seed for the cross-validation and percentage split (default: 1).

    -m file with cost matrix
    The name of a file containing a cost matrix.

    -l filename
    Loads classifier from the given file. In case the filename ends with ".xml",a PMML file is loaded or, if that fails, options are loaded from XML.

    -d filename
    Saves classifier built from the training data into the given file. In case the filename ends with ".xml" the options are saved XML, not the model.

    -v
    Outputs no statistics for the training data.

    -o
    Outputs statistics only, not the classifier.

    -i
    Outputs detailed information-retrieval statistics per class.

    -k
    Outputs information-theoretic statistics.

    -classifications "weka.classifiers.evaluation.output.prediction.AbstractOutput + options"
    Uses the specified class for generating the classification output. E.g.: weka.classifiers.evaluation.output.prediction.PlainText or : weka.classifiers.evaluation.output.prediction.CSV -p range
    Outputs predictions for test instances (or the train instances if no test instances provided and -no-cv is used), along with the attributes in the specified range (and nothing else). Use '-p 0' if no attributes are desired.

    Deprecated: use "-classifications ..." instead.

    -distribution
    Outputs the distribution instead of only the prediction in conjunction with the '-p' option (only nominal classes).

    Deprecated: use "-classifications ..." instead.

    -no-predictions
    Turns off the collection of predictions in order to conserve memory.

    -r
    Outputs cumulative margin distribution (and nothing else).

    -g
    Only for classifiers that implement "Graphable." Outputs the graph representation of the classifier (and nothing else).

    -xml filename | xml-string
    Retrieves the options from the XML-data instead of the command line.

    Parameters:
      `classifier` - machine learning classifier
      `options` - the array of string containing the options
    Returns:
      a string describing the results
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### evaluateModel

    public double[] evaluateModel(Classifier classifier, Instances data, Object... forPredictionsPrinting) throws Exception
    Evaluates the classifier on a given set of instances. Note that the data must have exactly the same format (e.g. order of attributes) as the data used to train the classifier! Otherwise the results will generally be meaningless.
    Parameters:
      `classifier` - machine learning classifier
      `data` - set of test instances for evaluation
      `forPredictionsPrinting` - varargs parameter that, if supplied, is expected to hold a weka.classifiers.evaluation.output.prediction.AbstractOutput object
    Returns:
      the predictions
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### evaluationForSingleInstance

    public double evaluationForSingleInstance(double[] dist, Instance instance, boolean storePredictions) throws Exception
    Evaluates the supplied distribution on a single instance.
    Parameters:
      `dist` - the supplied distribution
      `instance` - the test instance to be classified
      `storePredictions` - whether to store predictions for nominal classifier
    Returns:
      the prediction
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### evaluateModelOnceAndRecordPrediction

    public double evaluateModelOnceAndRecordPrediction(Classifier classifier, Instance instance) throws Exception
    Evaluates the classifier on a single instance and records the prediction.
    Parameters:
      `classifier` - machine learning classifier
      `instance` - the test instance to be classified
    Returns:
      the prediction made by the clasifier
    Throws:
      `Exception` - if model could not be evaluated successfully or the data contains string attributes

  - ### evaluateModelOnce

    public double evaluateModelOnce(Classifier classifier, Instance instance) throws Exception
    Evaluates the classifier on a single instance.
    Parameters:
      `classifier` - machine learning classifier
      `instance` - the test instance to be classified
    Returns:
      the prediction made by the clasifier
    Throws:
      `Exception` - if model could not be evaluated successfully or the data contains string attributes

  - ### evaluateModelOnce

    public double evaluateModelOnce(double[] dist, Instance instance) throws Exception
    Evaluates the supplied distribution on a single instance.
    Parameters:
      `dist` - the supplied distribution
      `instance` - the test instance to be classified
    Returns:
      the prediction
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### evaluateModelOnceAndRecordPrediction

    public double evaluateModelOnceAndRecordPrediction(double[] dist, Instance instance) throws Exception
    Evaluates the supplied distribution on a single instance.
    Parameters:
      `dist` - the supplied distribution
      `instance` - the test instance to be classified
    Returns:
      the prediction
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### evaluateModelOnce

    public void evaluateModelOnce(double prediction, Instance instance) throws Exception
    Evaluates the supplied prediction on a single instance.
    Parameters:
      `prediction` - the supplied prediction
      `instance` - the test instance to be classified
    Throws:
      `Exception` - if model could not be evaluated successfully

  - ### predictions

    public ArrayList<Prediction> predictions()
    Returns the predictions that have been collected.
    Returns:
      a reference to the FastVector containing the predictions that have been collected. This should be null if no predictions have been collected.

  - ### wekaStaticWrapper

    public static String wekaStaticWrapper(Sourcable classifier, String className) throws Exception
    Wraps a static classifier in enough source to test using the weka class libraries.
    Parameters:
      `classifier` - a Sourcable Classifier
      `className` - the name to give to the source code class
    Returns:
      the source for a static classifier that can be tested with weka libraries.
    Throws:
      `Exception` - if code-generation fails

  - ### numInstances

    public final double numInstances()
    Gets the number of test instances that had a known class value (actually the sum of the weights of test instances with known class value).
    Returns:
      the number of test instances with known class

  - ### coverageOfTestCasesByPredictedRegions

    public final double coverageOfTestCasesByPredictedRegions()
    Gets the coverage of the test cases by the predicted regions at the confidence level specified when evaluation was performed.
    Returns:
      the coverage of the test cases by the predicted regions

  - ### sizeOfPredictedRegions

    public final double sizeOfPredictedRegions()
    Gets the average size of the predicted regions, relative to the range of the target in the training data, at the confidence level specified when evaluation was performed.
    Returns:
      the average size of the predicted regions

  - ### incorrect

    public final double incorrect()
    Gets the number of instances incorrectly classified (that is, for which an incorrect prediction was made). (Actually the sum of the weights of these instances)
    Returns:
      the number of incorrectly classified instances

  - ### pctIncorrect

    public final double pctIncorrect()
    Gets the percentage of instances incorrectly classified (that is, for which an incorrect prediction was made).
    Returns:
      the percent of incorrectly classified instances (between 0 and 100)

  - ### totalCost

    public final double totalCost()
    Gets the total cost, that is, the cost of each prediction times the weight of the instance, summed over all instances.
    Returns:
      the total cost

  - ### avgCost

    public final double avgCost()
    Gets the average cost, that is, total cost of misclassifications (incorrect plus unclassified) over the total number of instances.
    Returns:
      the average cost.

  - ### correct

    public final double correct()
    Gets the number of instances correctly classified (that is, for which a correct prediction was made). (Actually the sum of the weights of these instances)
    Returns:
      the number of correctly classified instances

  - ### pctCorrect

    public final double pctCorrect()
    Gets the percentage of instances correctly classified (that is, for which a correct prediction was made).
    Returns:
      the percent of correctly classified instances (between 0 and 100)

  - ### unclassified

    public final double unclassified()
    Gets the number of instances not classified (that is, for which no prediction was made by the classifier). (Actually the sum of the weights of these instances)
    Returns:
      the number of unclassified instances

  - ### pctUnclassified

    public final double pctUnclassified()
    Gets the percentage of instances not classified (that is, for which no prediction was made by the classifier).
    Returns:
      the percent of unclassified instances (between 0 and 100)

  - ### errorRate

    public final double errorRate()
    Returns the estimated error rate or the root mean squared error (if the class is numeric). If a cost matrix was given this error rate gives the average cost.
    Returns:
      the estimated error rate (between 0 and 1, or between 0 and maximum cost)

  - ### kappa

    public final double kappa()
    Returns value of kappa statistic if class is nominal.
    Returns:
      the value of the kappa statistic

  - ### getRevision

    public String getRevision()
    Description copied from interface: `RevisionHandler`
    Returns the revision string.
    Specified by:
      `getRevision` in interface `RevisionHandler`
    Returns:
      the revision

  - ### correlationCoefficient

    public final double correlationCoefficient() throws Exception
    Returns the correlation coefficient if the class is numeric.
    Returns:
      the correlation coefficient
    Throws:
      `Exception` - if class is not numeric

  - ### meanAbsoluteError

    public final double meanAbsoluteError()
    Returns the mean absolute error. Refers to the error of the predicted values for numeric classes, and the error of the predicted probability distribution for nominal classes.
    Returns:
      the mean absolute error

  - ### meanPriorAbsoluteError

    public final double meanPriorAbsoluteError()
    Returns the mean absolute error of the prior.
    Returns:
      the mean absolute error

  - ### relativeAbsoluteError

    public final double relativeAbsoluteError() throws Exception
    Returns the relative absolute error.
    Returns:
      the relative absolute error
    Throws:
      `Exception` - if it can't be computed

  - ### rootMeanSquaredError

    public final double rootMeanSquaredError()
    Returns the root mean squared error.
    Returns:
      the root mean squared error

  - ### rootMeanPriorSquaredError

    public final double rootMeanPriorSquaredError()
    Returns the root mean prior squared error.
    Returns:
      the root mean prior squared error

  - ### rootRelativeSquaredError

    public final double rootRelativeSquaredError()
    Returns the root relative squared error if the class is numeric.
    Returns:
      the root relative squared error

  - ### priorEntropy

    public final double priorEntropy() throws Exception
    Calculate the entropy of the prior distribution.
    Returns:
      the entropy of the prior distribution
    Throws:
      `Exception` - if the class is not nominal

  - ### KBInformation

    public final double KBInformation() throws Exception
    Return the total Kononenko & Bratko Information score in bits.
    Returns:
      the K&B information score
    Throws:
      `Exception` - if the class is not nominal

  - ### KBMeanInformation

    public final double KBMeanInformation() throws Exception
    Return the Kononenko & Bratko Information score in bits per instance.
    Returns:
      the K&B information score
    Throws:
      `Exception` - if the class is not nominal

  - ### KBRelativeInformation

    public final double KBRelativeInformation() throws Exception
    Return the Kononenko & Bratko Relative Information score.
    Returns:
      the K&B relative information score
    Throws:
      `Exception` - if the class is not nominal

  - ### SFPriorEntropy

    public final double SFPriorEntropy()
    Returns the total entropy for the null model.
    Returns:
      the total null model entropy

  - ### SFMeanPriorEntropy

    public final double SFMeanPriorEntropy()
    Returns the entropy per instance for the null model.
    Returns:
      the null model entropy per instance

  - ### SFSchemeEntropy

    public final double SFSchemeEntropy()
    Returns the total entropy for the scheme.
    Returns:
      the total scheme entropy

  - ### SFMeanSchemeEntropy

    public final double SFMeanSchemeEntropy()
    Returns the entropy per instance for the scheme.
    Returns:
      the scheme entropy per instance

  - ### SFEntropyGain

    public final double SFEntropyGain()
    Returns the total SF, which is the null model entropy minus the scheme entropy.
    Returns:
      the total SF

  - ### SFMeanEntropyGain

    public final double SFMeanEntropyGain()
    Returns the SF per instance, which is the null model entropy minus the scheme entropy, per instance.
    Returns:
      the SF per instance

  - ### toCumulativeMarginDistributionString

    public String toCumulativeMarginDistributionString() throws Exception
    Output the cumulative margin distribution as a string suitable for input for gnuplot or similar package.
    Returns:
      the cumulative margin distribution
    Throws:
      `Exception` - if the class attribute is nominal

  - ### toSummaryString

    public String toSummaryString()
    Calls toSummaryString() with no title and no complexity stats.
    Specified by:
      `toSummaryString` in interface `Summarizable`
    Returns:
      a summary description of the classifier evaluation

  - ### toSummaryString

    public String toSummaryString(boolean printComplexityStatistics)
    Calls toSummaryString() with a default title.
    Parameters:
      `printComplexityStatistics` - if true, complexity statistics are returned as well
    Returns:
      the summary string

  - ### toSummaryString

    public String toSummaryString(String title, boolean printComplexityStatistics)
    Outputs the performance statistics in summary form. Lists number (and percentage) of instances classified correctly, incorrectly and unclassified. Outputs the total number of instances classified, and the number of instances (if any) that had no class value provided.
    Parameters:
      `title` - the title for the statistics
      `printComplexityStatistics` - if true, complexity statistics are returned as well
    Returns:
      the summary as a String

  - ### toMatrixString

    public String toMatrixString() throws Exception
    Calls toMatrixString() with a default title.
    Returns:
      the confusion matrix as a string
    Throws:
      `Exception` - if the class is numeric

  - ### toMatrixString

    public String toMatrixString(String title) throws Exception
    Outputs the performance statistics as a classification confusion matrix. For each class value, shows the distribution of predicted class values.
    Parameters:
      `title` - the title for the confusion matrix
    Returns:
      the confusion matrix as a String
    Throws:
      `Exception` - if the class is numeric

  - ### toClassDetailsString

    public String toClassDetailsString() throws Exception
    Generates a breakdown of the accuracy for each class (with default title), incorporating various information-retrieval statistics, such as true/false positive rate, precision/recall/F-Measure. Should be useful for ROC curves, recall/precision curves.
    Returns:
      the statistics presented as a string
    Throws:
      `Exception` - if class is not nominal

  - ### toClassDetailsString

    public String toClassDetailsString(String title) throws Exception
    Generates a breakdown of the accuracy for each class, incorporating various information-retrieval statistics, such as true/false positive rate, precision/recall/F-Measure. Should be useful for ROC curves, recall/precision curves.
    Parameters:
      `title` - the title to prepend the stats string with
    Returns:
      the statistics presented as a string
    Throws:
      `Exception` - if class is not nominal

  - ### numTruePositives

    public double numTruePositives(int classIndex)
    Calculate the number of true positives with respect to a particular class. This is defined as

         correctly classified positives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the true positive rate

  - ### truePositiveRate

    public double truePositiveRate(int classIndex)
    Calculate the true positive rate with respect to a particular class. This is defined as

         correctly classified positives
         ------------------------------
               total positives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the true positive rate

  - ### weightedTruePositiveRate

    public double weightedTruePositiveRate()
    Calculates the weighted (by class size) true positive rate.
    Returns:
      the weighted true positive rate.

  - ### numTrueNegatives

    public double numTrueNegatives(int classIndex)
    Calculate the number of true negatives with respect to a particular class. This is defined as

         correctly classified negatives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the true positive rate

  - ### trueNegativeRate

    public double trueNegativeRate(int classIndex)
    Calculate the true negative rate with respect to a particular class. This is defined as

         correctly classified negatives
         ------------------------------
               total negatives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the true positive rate

  - ### weightedTrueNegativeRate

    public double weightedTrueNegativeRate()
    Calculates the weighted (by class size) true negative rate.
    Returns:
      the weighted true negative rate.

  - ### numFalsePositives

    public double numFalsePositives(int classIndex)
    Calculate number of false positives with respect to a particular class. This is defined as

         incorrectly classified negatives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the false positive rate

  - ### falsePositiveRate

    public double falsePositiveRate(int classIndex)
    Calculate the false positive rate with respect to a particular class. This is defined as

         incorrectly classified negatives
         --------------------------------
                total negatives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the false positive rate

  - ### weightedFalsePositiveRate

    public double weightedFalsePositiveRate()
    Calculates the weighted (by class size) false positive rate.
    Returns:
      the weighted false positive rate.

  - ### numFalseNegatives

    public double numFalseNegatives(int classIndex)
    Calculate number of false negatives with respect to a particular class. This is defined as

         incorrectly classified positives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the false positive rate

  - ### falseNegativeRate

    public double falseNegativeRate(int classIndex)
    Calculate the false negative rate with respect to a particular class. This is defined as

         incorrectly classified positives
         --------------------------------
                total positives

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the false positive rate

  - ### weightedFalseNegativeRate

    public double weightedFalseNegativeRate()
    Calculates the weighted (by class size) false negative rate.
    Returns:
      the weighted false negative rate.

  - ### matthewsCorrelationCoefficient

    public double matthewsCorrelationCoefficient(int classIndex)
    Calculates the matthews correlation coefficient (sometimes called phi coefficient) for the supplied class
    Parameters:
      `classIndex` - the index of the class to compute the matthews correlation coefficient for
    Returns:
      the mathews correlation coefficient

  - ### weightedMatthewsCorrelation

    public double weightedMatthewsCorrelation()
    Calculates the weighted (by class size) matthews correlation coefficient.
    Returns:
      the weighted matthews correlation coefficient.

  - ### recall

    public double recall(int classIndex)
    Calculate the recall with respect to a particular class. This is defined as

         correctly classified positives
         ------------------------------
               total positives

    (Which is also the same as the truePositiveRate.)
    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the recall

  - ### weightedRecall

    public double weightedRecall()
    Calculates the weighted (by class size) recall.
    Returns:
      the weighted recall.

  - ### precision

    public double precision(int classIndex)
    Calculate the precision with respect to a particular class. This is defined as

         correctly classified positives
         ------------------------------
          total predicted as positive

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the precision

  - ### weightedPrecision

    public double weightedPrecision()
    Calculates the weighted (by class size) precision.
    Returns:
      the weighted precision.

  - ### fMeasure

    public double fMeasure(int classIndex)
    Calculate the F-Measure with respect to a particular class. This is defined as

         2 * recall * precision
         ----------------------
           recall + precision

    Parameters:
      `classIndex` - the index of the class to consider as "positive"
    Returns:
      the F-Measure

  - ### weightedFMeasure

    public double weightedFMeasure()
    Calculates the macro weighted (by class size) average F-Measure.
    Returns:
      the weighted F-Measure.

  - ### unweightedMacroFmeasure

    public double unweightedMacroFmeasure()
    Unweighted macro-averaged F-measure. If some classes not present in the test set, they're just skipped (since recall is undefined there anyway) .
    Returns:
      unweighted macro-averaged F-measure.

  - ### unweightedMicroFmeasure

    public double unweightedMicroFmeasure()
    Unweighted micro-averaged F-measure. If some classes not present in the test set, they have no effect. Note: if the test set is *single-label*, then this is the same as accuracy.
    Returns:
      unweighted micro-averaged F-measure.

  - ### setPriors

    public void setPriors(Instances train) throws Exception
    Sets the class prior probabilities.
    Parameters:
      `train` - the training instances used to determine the prior probabilities
    Throws:
      `Exception` - if the class attribute of the instances is not set

  - ### getClassPriors

    public double[] getClassPriors()
    Get the current weighted class counts.
    Returns:
      the weighted class counts

  - ### updatePriors

    public void updatePriors(Instance instance) throws Exception
    Updates the class prior probabilities or the mean respectively (when incrementally training).
    Parameters:
      `instance` - the new training instance seen
    Throws:
      `Exception` - if the class of the instance is not set

  - ### useNoPriors

    public void useNoPriors()
    disables the use of priors, e.g., in case of de-serialized schemes that have no access to the original training set, but are evaluated on a set set.

  - ### equals

    public boolean equals(Object obj)
    Tests whether the current evaluation object is equal to another evaluation object.
    Overrides:
      `equals` in class `Object`
    Parameters:
      `obj` - the object to compare against
    Returns:
      true if the two objects are equal

  - ### main

    public static void main(String[] args)
    A test method for this class. Just extracts the first command line argument as a classifier class name and calls evaluateModel.
    Parameters:
      `args` - an array of command line arguments, the first of which must be the class name of a classifier.