FScore

java.lang.Object
- smile.validation.metric.FScore

All Implemented Interfaces:

java.io.Serializable, ClassificationMetric
```
public class FScore
extends java.lang.Object
implements ClassificationMetric
```
The F-score (or F-measure) considers both the precision and the recall of the test to compute the score. The precision p is the number of correct positive results divided by the number of all positive results, and the recall r is the number of correct positive results divided by the number of positive results that should have been returned.
The traditional or balanced F-score (F1 score) is the harmonic mean of precision and recall, where an F1 score reaches its best value at 1 and worst at 0.
The general formula involves a positive real β so that F-score measures the effectiveness of retrieval with respect to a user who attaches β times as much importance to recall as precision.

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`static FScore`	`F1` The F_1 score, the harmonic mean of precision and recall.
`static FScore`	`F2` The F_2 score, which weighs recall higher than precision.
`static FScore`	`FHalf` The F_0.5 score, which weighs recall lower than precision.

Constructor Summary

Constructors
Constructor and Description

FScore()
Constructor of F1 score.

FScore(double beta)
Constructor of general F-score.

Constructors
Constructor and Description
`FScore()` Constructor of F1 score.
`FScore(double beta)` Constructor of general F-score.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static double`	`of(double beta, int[] truth, int[] prediction)` Calculates the F1 score.
`double`	`score(int[] truth, int[] prediction)` Returns a score to measure the quality of classification.
`java.lang.String`	`toString()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - F1
```
public static final FScore F1
```
    The F_1 score, the harmonic mean of precision and recall.
  - F2
```
public static final FScore F2
```
    The F_2 score, which weighs recall higher than precision.
  - FHalf
```
public static final FScore FHalf
```
    The F_0.5 score, which weighs recall lower than precision.
- Constructor Detail
  - FScore
```
public FScore()
```
    Constructor of F1 score.
  - FScore
```
public FScore(double beta)
```
    Constructor of general F-score.
    
    Parameters:
    
    beta - a positive value such that F-score measures the effectiveness of retrieval with respect to a user who attaches β times as much importance to recall as precision.
- Method Detail
  - score
```
public double score(int[] truth,
                    int[] prediction)
```
    Description copied from interface: ClassificationMetric
    
    Returns a score to measure the quality of classification.
    
    Specified by:
    
    score in interface ClassificationMetric
    
    Parameters:
    
    truth - the true class labels.
    
    prediction - the predicted class labels.
  - of
```
public static double of(double beta,
                        int[] truth,
                        int[] prediction)
```
    Calculates the F1 score.
    
    Parameters:
    
    beta - a positive value such that F-score measures the effectiveness of retrieval with respect to a user who attaches β times as much importance to recall as precision.
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class FScore

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

F1

F2

FHalf

Constructor Detail

FScore

FScore

Method Detail

score

of

toString