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ChiSquared Class Reference

#include <ChiSquared.h>

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.

References degreesOfFreedom(), lnProbability(), probability(), and value().

24 : theValue(value), theNDF(ndf) {}
float theNDF
Definition: ChiSquared.h:33
Definition: value.py:1
float theValue
Definition: ChiSquared.h:33

Member Function Documentation

float ChiSquared::degreesOfFreedom ( ) const

Definition at line 11 of file ChiSquared.cc.

References theNDF.

Referenced by ChiSquared(), lnProbability(), and probability().

12 {
13  return theNDF;
14 }
float theNDF
Definition: ChiSquared.h:33
float ChiSquared::lnProbability ( ) const

Definition at line 23 of file ChiSquared.cc.

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

Referenced by ChiSquared().

24 {
26 }
float LnChiSquaredProbability(double chiSquared, double nrDOF)
float degreesOfFreedom() const
Definition: ChiSquared.cc:11
float value() const
Definition: ChiSquared.cc:5
float ChiSquared::probability ( ) const

Definition at line 17 of file ChiSquared.cc.

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

Referenced by ChiSquared().

18 {
20 }
float degreesOfFreedom() const
Definition: ChiSquared.cc:11
float value() const
Definition: ChiSquared.cc:5
float ChiSquaredProbability(double chiSquared, double nrDOF)
float ChiSquared::value ( ) const

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().