de.lmu.ifi.dbs.elki.utilities.scaling.outlier

Class MultiplicativeInverseScaling

java.lang.Object

de.lmu.ifi.dbs.elki.utilities.scaling.outlier.MultiplicativeInverseScaling

All Implemented Interfaces:

OutlierScaling, ScalingFunction

@Reference(authors="Hans-Peter Kriegel, Peer Kr\u00f6ger, Erich Schubert, Arthur Zimek",
           title="Interpreting and Unifying Outlier Scores",
           booktitle="Proc. 11th SIAM International Conference on Data Mining (SDM 2011)",
           url="https://doi.org/10.1137/1.9781611972818.2",
           bibkey="DBLP:conf/sdm/KriegelKSZ11")
public class MultiplicativeInverseScaling
extends java.lang.Object
implements OutlierScaling

Scaling function to invert values by computing 1/x, but in a variation that maps the values to the [0:1] interval and avoiding division by 0.

The exact formula can be written as \[ 1 / (v \cdot \max_{x\neq 0}\frac{1}{|x|}) = \min_{x \neq 0}(|x|) / v \] with 1 / 0 := 1

Reference:

Hans-Peter Kriegel, Peer Kröger, Erich Schubert, Arthur Zimek
Interpreting and Unifying Outlier Scores
Proc. 11th SIAM International Conference on Data Mining (SDM 2011)

Since:

0.3

Author:

Erich Schubert

Field Summary

Fields

Modifier and Type	Field and Description
(package private) double	scaleval Scaling value, set by prepare(de.lmu.ifi.dbs.elki.result.outlier.OutlierResult).

Constructor Summary

Constructors

Constructor and Description
MultiplicativeInverseScaling() Constructor.

Method Summary

Modifier and Type	Method and Description
double	getMax() Get maximum resulting value.
double	getMin() Get minimum resulting value.
double	getScaled(double value) Transform a given value using the scaling function.
<A> void	prepare(A array, NumberArrayAdapter<?,A> adapter) Prepare is called once for each data set, before getScaled() will be called.
void	prepare(OutlierResult or) Prepare is called once for each data set, before getScaled() will be called.

Methods inherited from class java.lang.Object

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

Field Detail

scaleval

double scaleval

Scaling value, set by prepare(de.lmu.ifi.dbs.elki.result.outlier.OutlierResult).

Constructor Detail

MultiplicativeInverseScaling

public MultiplicativeInverseScaling()

Constructor.

Method Detail

getScaled

public double getScaled(double value)

Description copied from interface: ScalingFunction

Transform a given value using the scaling function.

Specified by:

getScaled in interface ScalingFunction

Parameters:

value - Original value

Returns:

Scaled value

prepare

public void prepare(OutlierResult or)

Description copied from interface: OutlierScaling

Prepare is called once for each data set, before getScaled() will be called. This function can be used to extract global parameters such as means, minimums or maximums from the outlier scores.

Specified by:

prepare in interface OutlierScaling

Parameters:

or - Outlier result to use

prepare

public <A> void prepare(A array,
                        NumberArrayAdapter<?,A> adapter)

Description copied from interface: OutlierScaling

Prepare is called once for each data set, before getScaled() will be called. This function can be used to extract global parameters such as means, minimums or maximums from the score array. The method using a full OutlierResult is preferred, as it will allow access to the metadata.

Specified by:

prepare in interface OutlierScaling

Parameters:

array - Data to process

adapter - Array adapter

getMin

public double getMin()

Description copied from interface: ScalingFunction

Get minimum resulting value. May be Double.NaN or Double.NEGATIVE_INFINITY.

Specified by:

getMin in interface ScalingFunction

Returns:

Minimum resulting value.

getMax

public double getMax()

Description copied from interface: ScalingFunction

Get maximum resulting value. May be Double.NaN or Double.POSITIVE_INFINITY.

Specified by:

getMax in interface ScalingFunction

Returns:

Maximum resulting value.