Representation of a confusion matrix. More...

#include <cvb/polimago/confusion_matrix.hpp>

Public Member Functions
	ConfusionMatrix (const ClassificationTestResult &res)
	Constructor. More...

int	TotalSamples (int classIndex) const
	Determine the total number of samples available for a given class. More...

int	TotalSamples () const
	Return the total sample count. More...

int	TotalCorrect (int classIndex) const
	Number of correctly classified samples in a given class. More...

int	TotalCorrect () const
	Overall number of correctly classified samples. More...

int	TotalErrors (int classIndex) const
	Determine the total number of errors made for a given class. More...

int	TotalErrors () const
	Determine the total error count. More...

int	TotalRejects () const
	Total number of rejected items (i.e. items that have a confidence of less than the currently set threshold, no matter if they are correctly classified or not). More...

std::vector< PredictionResult >	Rejects (int classIndex) const
	Get the rejects for a given class. More...

int	NumClasses () const noexcept
	Number of classes in this matrix. More...

std::vector< PredictionResult >	At (int trueClass, int predictedClass) const
	Access the results stored in the confusion matrix. More...

double	ConfidenceThreshold () const noexcept
	Get threshold to be taken into account when determining the confusion matrix. More...

void	SetConfidenceThreshold (double threshold)
	Set the threshold to be taken into account when determining the confusion matrix. More...

Detailed Description

Representation of a confusion matrix.

A confusion matrix is a matrix that gives detailed information about the kind of mistakes that occurred during a leave-out or sample test.

Constructor & Destructor Documentation

◆ ConfusionMatrix()

ConfusionMatrix ( const ClassificationTestResult & res )

inline

Constructor.

Parameters

[in] res ClassificationTestResult for which to calculate the confusion matrix.

Exceptions

Any	exception derived from std::exception including CvbException.

Member Function Documentation

◆ At()

std::vector< PredictionResult > At	(	int	trueClass,
		int	predictedClass
	)		const

inline

Access the results stored in the confusion matrix.

Parameters

[in]	trueClass	True class index.
[in]	predictedClass	Prediction result.

Returns: Confusion matrix value.

Exceptions

Any	exception derived from std::exception including CvbException.

The confusion matrix is to be read as follows: The first index (usually considered the line index) corresponds to the true class index, whereas the 2nd index (column index) is the prediction result. Example: Consider the result counts in a confusion matrix for a two-class problem to be distributed as follows: A B A 10 3 B 1 6 This means that 10 samples of class A have been correctly identified as class A, while 3 samples of class A have been misclassified as class B. Likewise, one sample of class B has been misclassified as class A, while 6 samples of class B have been identified correctly.

◆ ConfidenceThreshold()

double ConfidenceThreshold ( ) const

inlinenoexcept

Get threshold to be taken into account when determining the confusion matrix.

Returns: The confidence threshold.

Exceptions

Does	not throw any exception.

◆ NumClasses()

int NumClasses ( ) const

inlinenoexcept

Number of classes in this matrix.

Returns: Class count.

Exceptions

Does	not throw any exception.

◆ Rejects()

std::vector< PredictionResult > Rejects ( int classIndex ) const

inline

Get the rejects for a given class.

Parameters

[in] classIndex Index of the class for which to retrieve the rejected results.

Returns: The rejected results for given class.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ SetConfidenceThreshold()

void SetConfidenceThreshold ( double threshold )

inline

Set the threshold to be taken into account when determining the confusion matrix.

Parameters

[in] threshold The confidence threshold.

Exceptions

Any	exception derived from std::exception including CvbException.

If the threshold is modified, the whole matrix will be updated accordingly, so setting this property may be a costly action.

◆ TotalCorrect() [1/2]

int TotalCorrect ( ) const

inline

Overall number of correctly classified samples.

Returns: Total number of correct results.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ TotalCorrect() [2/2]

int TotalCorrect ( int classIndex ) const

inline

Number of correctly classified samples in a given class.

Parameters

[in] classIndex Index of the class for which to query the number of correct classifications.

Returns: Total number of correct classifications for the class referred to by the classIndex parameter.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ TotalErrors() [1/2]

int TotalErrors ( ) const

inline

Determine the total error count.

Returns: Total error count over all classes.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ TotalErrors() [2/2]

int TotalErrors ( int classIndex ) const

inline

Determine the total number of errors made for a given class.

Parameters

[in] classIndex Index of the class for which to query the number of incorrect results.

Returns: The number of incorrect results for the class referred to by classIndex parameter.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ TotalRejects()

int TotalRejects ( ) const

inline

Total number of rejected items (i.e. items that have a confidence of less than the currently set threshold, no matter if they are correctly classified or not).

Returns: Total number of rejects over all classes.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ TotalSamples() [1/2]

int TotalSamples ( ) const

inline

Return the total sample count.

Returns: Total number of samples over all classes.

Exceptions

Any	exception derived from std::exception including CvbException.

◆ TotalSamples() [2/2]

int TotalSamples ( int classIndex ) const

inline

Determine the total number of samples available for a given class.

Parameters

[in] classIndex Index of the class for which to query the number of samples.

Returns: Total number of samples in the class referred to by the classIndex parameter.

Exceptions

Any	exception derived from std::exception including CvbException.

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ConfusionMatrix()

Member Function Documentation

◆ At()

◆ ConfidenceThreshold()

◆ NumClasses()

◆ Rejects()

◆ SetConfidenceThreshold()

◆ TotalCorrect() [1/2]

◆ TotalCorrect() [2/2]

◆ TotalErrors() [1/2]

◆ TotalErrors() [2/2]

◆ TotalRejects()

◆ TotalSamples() [1/2]

◆ TotalSamples() [2/2]