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Public Member Functions | Private Attributes

ChiSquared Class Reference

#include <ChiSquared.h>

List of all members.

Public Member Functions

 ChiSquared (float value, float ndf)
float degreesOfFreedom () const
float lnProbability () const
float probability () const
float value () const

Private Attributes

float theNDF
float theValue

Detailed Description

Constructed with total chi-squared value `value` and number of degrees of freedom `ndf`.

Computes chi-squared upper tail probability, i.e. the probability that an observation, correctly described by a model with nrDOF, will give rise to a chi-squared larger than the one observed. From this, one can interpret this probability as how likely it is to observe as high (or higher) a chi-squared.

Also computes the natural logarithm of that probability, useful to compare very unlikely events, for which the probability is rounded off to 0.

Definition at line 20 of file ChiSquared.h.


Constructor & Destructor Documentation

ChiSquared::ChiSquared ( float  value,
float  ndf 
) [inline]

Definition at line 24 of file ChiSquared.h.

: theValue(value), theNDF(ndf) {}

Member Function Documentation

float ChiSquared::degreesOfFreedom ( ) const

Definition at line 11 of file ChiSquared.cc.

References theNDF.

Referenced by lnProbability(), and probability().

{
  return theNDF;
}
float ChiSquared::lnProbability ( ) const

Definition at line 23 of file ChiSquared.cc.

References degreesOfFreedom(), LnChiSquaredProbability(), and value().

float ChiSquared::probability ( ) const

Definition at line 17 of file ChiSquared.cc.

References ChiSquaredProbability(), degreesOfFreedom(), and value().

float ChiSquared::value ( ) const

Definition at line 5 of file ChiSquared.cc.

References theValue.

Referenced by lnProbability(), and probability().

{
  return theValue;
}

Member Data Documentation

float ChiSquared::theNDF [private]

Definition at line 33 of file ChiSquared.h.

Referenced by degreesOfFreedom().

float ChiSquared::theValue [private]

Definition at line 33 of file ChiSquared.h.

Referenced by value().