weka.classifiers.evaluation

Class EvaluationMetricHelper

java.lang.Object

weka.classifiers.evaluation.EvaluationMetricHelper

public class EvaluationMetricHelper
extends java.lang.Object

Helper routines for extracting metric values from built-in and plugin evaluation metrics.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.Map<java.lang.String,java.lang.Integer>	m_builtin A lookup for built-in metrics
protected Evaluation	m_eval The Evaluation object to extract built-in and plugin metrics from
protected java.util.Map<java.lang.String,AbstractEvaluationMetric>	m_pluginMetrics A lookup for plugin metrics

Constructor Summary

Constructors

Constructor and Description
EvaluationMetricHelper(Evaluation eval) Construct a new EvaluationMetricHelper

Method Summary

Modifier and Type	Method and Description
protected boolean	builtInMetricIsMaximisable(int metricIndex) Returns true if the specified built-in metric is maximisable
static java.util.List<java.lang.String>	getAllMetricNames() Get a list of all available evaluation metric names
static java.util.List<java.lang.String>	getBuiltInMetricNames() Get a list of built-in metric names
protected double	getBuiltinMetricValue(int metricIndex, int... classValIndex) Gets the value of a built-in metric
double	getNamedMetric(java.lang.String statName, int... classValIndex) Gets the value of a named metric.
double[]	getNamedMetricThresholds(java.lang.String statName) Gets the thresholds produced by the metric, if the metric implements ThresholdProducingMetric.
static java.util.List<java.lang.String>	getPluginMetricNames() Get a list of plugin metric names
protected double	getPluginMetricValue(AbstractEvaluationMetric m, java.lang.String statName, int... classValIndex) Get the value of a plugin metric
protected void	initializeWithPluginMetrics() Initializes the plugin lookup
boolean	metricIsMaximisable(java.lang.String statName) Returns true if the named metric is maximisable
protected boolean	pluginMetricIsMaximisable(AbstractEvaluationMetric m, java.lang.String statName) Returns true if the named statistic is maximisable
void	setEvaluation(Evaluation eval) Sets the Evaluation object to use

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_eval

protected Evaluation m_eval

The Evaluation object to extract built-in and plugin metrics from

m_builtin

protected java.util.Map<java.lang.String,java.lang.Integer> m_builtin

A lookup for built-in metrics

m_pluginMetrics

protected java.util.Map<java.lang.String,AbstractEvaluationMetric> m_pluginMetrics

A lookup for plugin metrics

Constructor Detail

EvaluationMetricHelper

public EvaluationMetricHelper(Evaluation eval)

Construct a new EvaluationMetricHelper

Parameters:

eval - the Evaluation object to use

Method Detail

setEvaluation

public void setEvaluation(Evaluation eval)

Sets the Evaluation object to use

Parameters:

eval - the Evaluation object to use

initializeWithPluginMetrics

protected void initializeWithPluginMetrics()

Initializes the plugin lookup

getBuiltInMetricNames

public static java.util.List<java.lang.String> getBuiltInMetricNames()

Get a list of built-in metric names

Returns:

a list of built-in metric names

getPluginMetricNames

public static java.util.List<java.lang.String> getPluginMetricNames()

Get a list of plugin metric names

Returns:

a list of plugin metric names

getAllMetricNames

public static java.util.List<java.lang.String> getAllMetricNames()

Get a list of all available evaluation metric names

Returns:

a list of all available evaluation metric names

builtInMetricIsMaximisable

protected boolean builtInMetricIsMaximisable(int metricIndex)
                                      throws java.lang.Exception

Returns true if the specified built-in metric is maximisable

Parameters:

metricIndex - the index of metric

Returns:

true if the metric in question is optimum at a maximal value

Throws:

java.lang.Exception - if the metric is not a known built-in metric

getBuiltinMetricValue

protected double getBuiltinMetricValue(int metricIndex,
                                       int... classValIndex)
                                throws java.lang.Exception

Gets the value of a built-in metric

Parameters:

metricIndex - the index of the metric

classValIndex - the optional class value index

Returns:

the value of the metric

Throws:

java.lang.Exception - if the metric is not a known built-in metric

getPluginMetricValue

protected double getPluginMetricValue(AbstractEvaluationMetric m,
                                      java.lang.String statName,
                                      int... classValIndex)
                               throws java.lang.Exception

Get the value of a plugin metric

Parameters:

m - the metric to get the value from

statName - the name of the statistic to get the value of

classValIndex - the optional class value index

Returns:

the value of the metric

Throws:

java.lang.Exception - if a problem occurs

pluginMetricIsMaximisable

protected boolean pluginMetricIsMaximisable(AbstractEvaluationMetric m,
                                            java.lang.String statName)

Returns true if the named statistic is maximisable

Parameters:

m - the metric to check

statName - the name of the statistic to check

Returns:

true if the metric in question is optimum at a maximal value

getNamedMetric

public double getNamedMetric(java.lang.String statName,
                             int... classValIndex)
                      throws java.lang.Exception

Gets the value of a named metric. For information retrieval metrics if a class value index is not supplied then the class weighted variant is returned.

Parameters:

statName - the name of the metric/statistic to get

classValIndex - the optional class value index

Returns:

the value of the metric

Throws:

java.lang.Exception - if the metric/stat is unknown or a problem occurs

getNamedMetricThresholds

public double[] getNamedMetricThresholds(java.lang.String statName)
                                  throws java.lang.Exception

Gets the thresholds produced by the metric, if the metric implements ThresholdProducingMetric.

Parameters:

statName - the name of the metric/statistic to get

Returns:

the thresholds, null if metric does not produce any

Throws:

java.lang.Exception - if the metric/stat is unknown or a problem occurs

metricIsMaximisable

public boolean metricIsMaximisable(java.lang.String statName)
                            throws java.lang.Exception

Returns true if the named metric is maximisable

Parameters:

statName - the name of the metric/statistic to check

Returns:

true if the metric in question is optimum at a maximal value

Throws:

java.lang.Exception - if a problem occurs