edu.ucla.stat.SOCR.distributions
Class ErlangDistribution

java.lang.Object
  extended by edu.ucla.stat.SOCR.core.SOCRValueSettable
      extended by edu.ucla.stat.SOCR.core.Distribution
          extended by edu.ucla.stat.SOCR.distributions.ErlangDistribution
All Implemented Interfaces:
IValueSettable, Pluginable, java.util.Observer

public class ErlangDistribution
extends Distribution

A Java implmentation of the Erlang distribution with specified Scale (scale) and shape (shape) parameters http://mathworld.wolfram.com/ErlangDistribution.html .


Field Summary
 
Fields inherited from class edu.ucla.stat.SOCR.core.Distribution
applet, CONTINUOUS, DISCRETE, MAXMGFXVAL, MAXMGFYVAL, MINMGFXVAL, MIXED, name
 
Constructor Summary
ErlangDistribution()
          Default constructor: creates an Erlang distribution with scale and shape parameters equal to 1
ErlangDistribution(double[] distData)
          Constructor: creates an Erlang distribution from a sample data series and estimates the scale (a) and shape (b) parameters.
ErlangDistribution(double a, int b)
          Constructor: creates an Erlang distribution with scale (a) and shape (b) parameters.
ErlangDistribution(float[] distData)
          Constructor: creates an Erlang distribution from a sample data series and estimates the scale (a) and shape (b) parameters.
 
Method Summary
 double getCDF(double x)
          Compute the cumulative distribution function.
 double getDensity(double x)
          Define the Erlang getDensity function
 double getMaxDensity()
          Compute the maximum getDensity
 double getMean()
          Compute the mean in closed form
 double getMGF(double t)
          Computes the moment generating function in closed form for a parameter t which lies in the domain of the distribution.
 double getMode()
          Compute the mean in closed form
 java.lang.String getOnlineDescription()
          This method returns an online description of this distribution.
 double getScale()
          Get the scale paramter
 double getSD()
          Compute the variance in closed form
 int getShape()
          Get the shape parameter
 double getVariance()
          Compute the variance in closed form
 void initialize()
          used for some subclass to initialize before being used
 void paramEstimate(double[] distData)
          Overwrites the method in distribution for estimating parameters
 void setParameters(double a, int b)
          Set the parameters, compute the normalizing constant NormalizingConst, and specifies the interval and partition.
 void setScale(double a)
          Sets the scale parameter
 void setShape(int b)
          Sets the shape parameter
 void valueChanged()
           
 
Methods inherited from class edu.ucla.stat.SOCR.core.Distribution
addObserver, betaCDF, comb, factorial, findGFRoot, findRoot, gamma, gammaCDF, getDisplayPane, getDomain, getFailureRate, getGFDerivative, getGFSecondDerivative, getInstance, getLocalHelp, getMean, getMedian, getMgfDomain, getName, getPGF, getPGFDomain, getQuantile, getSampleMoment, getSOCRDistributionFunctors, getSOCRDistributions, getType, getVariance, inverseCDF, logGamma, perm, sampleMean, sampleVar, setApplet, setDomain, setDomain, setMGFDomain, setMGFDomain, setMGFParameters, setMGFParameters, setMGFParameters, setMGFParameters, setParameters, setPGFDomain, setPGFDomain, setPGFParameters, setPGFParameters, setPGFParameters, setPGFParameters, simulate, update, valueChanged
 
Methods inherited from class edu.ucla.stat.SOCR.core.SOCRValueSettable
createComponentSetter, createValueSetter, createValueSetter, createValueSetter, createValueSetter, getComponentSetter, getComponentSetters, getValueSetter, getValueSetters
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ErlangDistribution

public ErlangDistribution()
Default constructor: creates an Erlang distribution with scale and shape parameters equal to 1


ErlangDistribution

public ErlangDistribution(double a,
                          int b)
Constructor: creates an Erlang distribution with scale (a) and shape (b) parameters.


ErlangDistribution

public ErlangDistribution(double[] distData)
Constructor: creates an Erlang distribution from a sample data series and estimates the scale (a) and shape (b) parameters.


ErlangDistribution

public ErlangDistribution(float[] distData)
Constructor: creates an Erlang distribution from a sample data series and estimates the scale (a) and shape (b) parameters.

Method Detail

initialize

public void initialize()
Description copied from class: Distribution
used for some subclass to initialize before being used

Overrides:
initialize in class Distribution

valueChanged

public void valueChanged()
Overrides:
valueChanged in class Distribution

setParameters

public void setParameters(double a,
                          int b)
Set the parameters, compute the normalizing constant NormalizingConst, and specifies the interval and partition.


setScale

public void setScale(double a)
Sets the scale parameter


setShape

public void setShape(int b)
Sets the shape parameter


getScale

public double getScale()
Get the scale paramter


getShape

public int getShape()
Get the shape parameter


getDensity

public double getDensity(double x)
Define the Erlang getDensity function

Specified by:
getDensity in class Distribution

getMaxDensity

public double getMaxDensity()
Compute the maximum getDensity

Overrides:
getMaxDensity in class Distribution

getMean

public double getMean()
Compute the mean in closed form

Overrides:
getMean in class Distribution

getMode

public double getMode()
Compute the mean in closed form


paramEstimate

public void paramEstimate(double[] distData)
Overwrites the method in distribution for estimating parameters

Overrides:
paramEstimate in class Distribution

getVariance

public double getVariance()
Compute the variance in closed form

Overrides:
getVariance in class Distribution

getSD

public double getSD()
Compute the variance in closed form

Overrides:
getSD in class Distribution

getCDF

public double getCDF(double x)
Compute the cumulative distribution function.

Overrides:
getCDF in class Distribution

getMGF

public double getMGF(double t)
              throws ParameterOutOfBoundsException
Computes the moment generating function in closed form for a parameter t which lies in the domain of the distribution.

Overrides:
getMGF in class Distribution
Throws:
ParameterOutOfBoundsException

getOnlineDescription

public java.lang.String getOnlineDescription()
This method returns an online description of this distribution.

Overrides:
getOnlineDescription in class Distribution