dev.nm.stat.descriptive.moment.weighted

Class WeightedMean

java.lang.Object

dev.nm.stat.descriptive.moment.weighted.WeightedMean

All Implemented Interfaces:

Statistic

public class WeightedMean
extends Object
implements Statistic

The weighted mean is defined as \[ \bar{x} = \frac{ \sum_{i=1}^N w_i x_i}{\sum_{i=1}^N w_i} \]

See Also:

Wikipedia: Weighted mean

Constructor Summary

Constructors

Constructor and Description
WeightedMean()
WeightedMean(double[] data, double[] weights)

Method Summary

Modifier and Type	Method and Description
void	addData(double... data) Recompute the statistic with more data, incrementally if possible.
void	addData(double[] data, double[] weights)
long	N() Get the size of the sample.
double	sumOfWeights()
double	value() Get the value of the statistic.

Methods inherited from class java.lang.Object

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

Constructor Detail

WeightedMean

public WeightedMean()

WeightedMean

public WeightedMean(double[] data,
                    double[] weights)

Method Detail

addData

public void addData(double... data)

Description copied from interface: Statistic

Recompute the statistic with more data, incrementally if possible.

Specified by:

addData in interface Statistic

Parameters:

data - an array of new items

addData

public void addData(double[] data,
                    double[] weights)

N

public long N()

Description copied from interface: Statistic

Get the size of the sample.

Specified by:

N in interface Statistic

Returns:

the sample size

value

public double value()

Description copied from interface: Statistic

Get the value of the statistic.

Specified by:

value in interface Statistic

Returns:

the statistic

sumOfWeights

public double sumOfWeights()