org.forester.util
Class BasicDescriptiveStatistics

java.lang.Object
  extended by org.forester.util.BasicDescriptiveStatistics
All Implemented Interfaces:
DescriptiveStatistics

public class BasicDescriptiveStatistics
extends Object
implements DescriptiveStatistics


Field Summary
 
Fields inherited from interface org.forester.util.DescriptiveStatistics
PLUS_MINUS
 
Constructor Summary
BasicDescriptiveStatistics()
           
 
Method Summary
 void addValue(double d)
           
 double arithmeticMean()
           
 String asSummary()
           
 double coefficientOfVariation()
          Computes the coefficient of variation.
 double[] getDataAsDoubleArray()
           
 double getMax()
           
 double getMin()
           
 int getN()
           
 double getSum()
           
 String getSummaryAsString()
           
 double getValue(int index)
           
 double median()
           
 double midrange()
           
 double pearsonianSkewness()
          Determines relationship between the mean and the median.
static int[] performBinning(double[] values, double min, double max, int number_of_bins)
           
 double sampleStandardDeviation()
           
 double sampleStandardUnit(double value)
           
static double sampleStandardUnit(double value, double mean, double sd)
          Computes the sample standard unit (z-score).
 double sampleVariance()
           
 double standardErrorOfMean()
           
 double sumDeviations()
           
 String toString()
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

BasicDescriptiveStatistics

public BasicDescriptiveStatistics()
Method Detail

addValue

public void addValue(double d)
Specified by:
addValue in interface DescriptiveStatistics

arithmeticMean

public double arithmeticMean()
Specified by:
arithmeticMean in interface DescriptiveStatistics

asSummary

public String asSummary()
Specified by:
asSummary in interface DescriptiveStatistics

coefficientOfVariation

public double coefficientOfVariation()
Description copied from interface: DescriptiveStatistics
Computes the coefficient of variation. Used to express standard deviation independent of units of measure.

Specified by:
coefficientOfVariation in interface DescriptiveStatistics
Returns:

getDataAsDoubleArray

public double[] getDataAsDoubleArray()
Specified by:
getDataAsDoubleArray in interface DescriptiveStatistics

getMax

public double getMax()
Specified by:
getMax in interface DescriptiveStatistics

getMin

public double getMin()
Specified by:
getMin in interface DescriptiveStatistics

getN

public int getN()
Specified by:
getN in interface DescriptiveStatistics

getSum

public double getSum()
Specified by:
getSum in interface DescriptiveStatistics

getSummaryAsString

public String getSummaryAsString()
Specified by:
getSummaryAsString in interface DescriptiveStatistics

getValue

public double getValue(int index)
Specified by:
getValue in interface DescriptiveStatistics

median

public double median()
Specified by:
median in interface DescriptiveStatistics

midrange

public double midrange()
Specified by:
midrange in interface DescriptiveStatistics

pearsonianSkewness

public double pearsonianSkewness()
Description copied from interface: DescriptiveStatistics
Determines relationship between the mean and the median. This reflects how the data differs from the normal bell shaped distribution.

Specified by:
pearsonianSkewness in interface DescriptiveStatistics
Returns:

sampleStandardDeviation

public double sampleStandardDeviation()
Specified by:
sampleStandardDeviation in interface DescriptiveStatistics

sampleStandardUnit

public double sampleStandardUnit(double value)
Specified by:
sampleStandardUnit in interface DescriptiveStatistics

sampleVariance

public double sampleVariance()
Specified by:
sampleVariance in interface DescriptiveStatistics

standardErrorOfMean

public double standardErrorOfMean()
Specified by:
standardErrorOfMean in interface DescriptiveStatistics

sumDeviations

public double sumDeviations()
Specified by:
sumDeviations in interface DescriptiveStatistics

toString

public String toString()
Specified by:
toString in interface DescriptiveStatistics
Overrides:
toString in class Object

performBinning

public static int[] performBinning(double[] values,
                                   double min,
                                   double max,
                                   int number_of_bins)

sampleStandardUnit

public static double sampleStandardUnit(double value,
                                        double mean,
                                        double sd)
Computes the sample standard unit (z-score). Used to compute 'value' in terms of standard units. Note that 'value', 'mean' and 'sd' must be all from the same sample data.

Parameters:
value - a double in the sample for which
mean - the mean of the sample.
sd - The standard deviation of the sample.
Returns:
'value' in terms of standard units