yat  0.10.4pre
Public Member Functions | Protected Member Functions | Protected Attributes | Friends
theplu::yat::statistics::Averager4 Class Reference

class to calculate 1st, 2nd, 3rd, and 4th central moments More...

#include </scratch/bob/jari/tmp/pristine/yat-0.10.x/yat/statistics/Averager4.h>

Inheritance diagram for theplu::yat::statistics::Averager4:
theplu::yat::statistics::averager_base4< Averager4 > theplu::yat::statistics::averager_base3< Averager4 > theplu::yat::statistics::averager_base2< Averager4 > theplu::yat::statistics::averager_base< Averager4 >

List of all members.

Public Member Functions

 Averager4 (void)
 construct empty object
template<class Derived >
const Averager4operator+= (const averager_base4< Derived > &rhs)
 Third central moment.
double central_moment4 (void) const
 Fourth central moment.
double kurtosis (void) const
 Kurtosis.
double sum_x4_centered (void) const
 sum quadrupled centered
double central_moment3 (void) const
 Third central moment.
double skewness (void) const
 Skewness.
double sum_x3_centered (void) const
double cv (void) const
 Coeffient of variation.
double standard_error (void) const
double std (void) const
 The standard deviation is defined as the square root of the variance.
double std (double m) const
 The standard deviation is defined as the square root of the variance.
double sum_xx (void) const
double sum_xx_centered (void) const
double variance (double m) const
 The variance with known mean.
double variance (void) const
 The estimated variance.
double variance_unbiased (void) const
void add (double x, long n=1)
 add a data point
double mean (void) const
 mean
long n (void) const
 number of data points
void rescale (double a)
 Rescales the object.
void reset (void)
 Reset object.
double sum_x (void) const

Protected Member Functions

void add4 (double mean, double cm2, double cm3, double cm4, long int n)
void add4 (double delta)
double rescale4 (double x)
void add3 (double mean, double cm2, double cm3, long int n)
void add3 (double delta)
double rescale3 (double x)
void add2 (double mean, double cm2, long int n)
void add2 (double delta)
double rescale2 (double x)
void add1 (double x, long int n)
void add1 (double delta)
double rescale1 (double x)

Protected Attributes

double cm4_
 sum quadrupled centered
double cm3_
double cm2_
long int n_
double mean_
 mean

Friends

class averager_base< Averager4 >

Detailed Description

class to calculate 1st, 2nd, 3rd, and 4th central moments

Since:
yat 0.9

Member Function Documentation

void theplu::yat::statistics::averager_base< Averager4 >::add ( double  x,
long  n = 1 
)
inlineinherited

add a data point

Adding n number of data point(s) with value x.

void theplu::yat::statistics::averager_base< Averager4 >::add1 ( double  x,
long int  n 
)
protectedinherited

add n data points with value x

void theplu::yat::statistics::averager_base< Averager4 >::add1 ( double  delta)
protectedinherited

add one data point with value delta + mean()

void theplu::yat::statistics::averager_base2< Averager4 >::add2 ( double  mean,
double  cm2,
long int  n 
)
protectedinherited

add a set of n data points with mean mean and centralized squaed sum cm

void theplu::yat::statistics::averager_base2< Averager4 >::add2 ( double  delta)
protectedinherited

add one data point with value delta + mean()

void theplu::yat::statistics::averager_base3< Averager4 >::add3 ( double  mean,
double  cm2,
double  cm3,
long int  n 
)
protectedinherited

add a set of n data points with mean mean, sum squared centered cm2, and sum cubed centered cm3.

void theplu::yat::statistics::averager_base3< Averager4 >::add3 ( double  delta)
protectedinherited

add one data point with value delta + mean()

void theplu::yat::statistics::averager_base4< Averager4 >::add4 ( double  mean,
double  cm2,
double  cm3,
double  cm4,
long int  n 
)
protectedinherited

add a set of n data points with mean mean, sum squared centered cm2, sum cubed centered cm3, and sum quadrupled centered cm4.

void theplu::yat::statistics::averager_base4< Averager4 >::add4 ( double  delta)
protectedinherited

add one data point with value delta + mean()

double theplu::yat::statistics::averager_base3< Averager4 >::central_moment3 ( void  ) const
inlineinherited

Third central moment.

Third central moment is calculated as $ \frac{1}{n} \sum (x_i-m)^3 $ where m is the mean.

double theplu::yat::statistics::averager_base4< Averager4 >::central_moment4 ( void  ) const
inlineinherited

Fourth central moment.

Fourth central moment is calculated as $ \frac{1}{n} \sum (x_i-m)^4 $ where m is the mean.

double theplu::yat::statistics::averager_base2< Averager4 >::cv ( void  ) const
inlineinherited

Coeffient of variation.

Coeffient of variation (cv) is defined as ratio between the standard deviation and the mean: $ \frac{\sigma}{\mu} $.

Returns:
standard deviation divided by mean.
double theplu::yat::statistics::averager_base4< Averager4 >::kurtosis ( void  ) const
inlineinherited

Kurtosis.

Kurtosis is calculated as $ \frac{1}{n} \sum (x-m)^4 / \sigma^4 - 3.0 $ where m is mean, and $ \sigma $ is standard deviation.

Note:
this function uses a biased variance estimate [1/n] compared to kurtosis(utility::VectorBase&), which uses an unbiased variance estimate [1/(n-1)] and may thus give different results for small n.
double theplu::yat::statistics::averager_base< Averager4 >::mean ( void  ) const
inlineinherited

mean

Returns:
Mean of presented data, $ \frac{1}{n}\sum x_i $
long theplu::yat::statistics::averager_base< Averager4 >::n ( void  ) const
inlineinherited

number of data points

Returns:
Number of data points
template<class Derived >
const Averager4 & theplu::yat::statistics::Averager4::operator+= ( const averager_base4< Derived > &  rhs)

Third central moment.

   Access Averager that holds first and second moments
   \return  \form#241

Fourth central moment

   \return  \form#242
The kurtosis is calculated as \form#243 where \form#244@_fakenl and \form#245 are the fourth central moment and
variance, respectively.

\return kurtosis

\see central_moment4 and Averager::variance

\note This function uses a biased estimator of the variance
(see Averager::variance) whereas function
kurtosis(const utility::VectorBase&) uses an unbiased estimator
(Averger::variance_unbiased) and therefore the result may
differ for small \a N.
   The skewness is calculated as \form#246 where \form#247@_fakenl and \form#161 are the third central moment and
   standard deviation, respectively.

   \return skewness

   \see central_moment3 and Averager::std

   \note This function uses a biased estimator of the variance
   (see Averager::variance) whereas function 
   skewness(const utility::VectorBase&) uses an unbiased estimator
   (Averger::variance_unbiased) and therefore the result may
   differ for small \a N.
void theplu::yat::statistics::averager_base< Averager4 >::rescale ( double  a)
inlineinherited

Rescales the object.

$ \forall x_i \rightarrow a*x_i $,

double theplu::yat::statistics::averager_base< Averager4 >::rescale1 ( double  x)
protectedinherited

rescale as $ mean \rightarrow x mean $

double theplu::yat::statistics::averager_base2< Averager4 >::rescale2 ( double  x)
protectedinherited

rescales $ cm2 \rightarrow x^2 cm2 $ and calles rescale1(double)

double theplu::yat::statistics::averager_base3< Averager4 >::rescale3 ( double  x)
protectedinherited

rescales $ cm3 = x^3 cm3 $ and calles rescale2(double)

double theplu::yat::statistics::averager_base4< Averager4 >::rescale4 ( double  x)
protectedinherited

rescales $ cm4 = x^4 cm4 $ and calles rescale2(double)

void theplu::yat::statistics::averager_base< Averager4 >::reset ( void  )
inlineinherited

Reset object.

Restore Averager as if data were never added

double theplu::yat::statistics::averager_base3< Averager4 >::skewness ( void  ) const
inlineinherited

Skewness.

Skewness is calculated as $ \frac{1}{n} \sum (x_i-m) / \sigma^3 $ where $ \sigma $ is standard deviation.

Note:
this function uses a biased variance estimate [1/n] compared to skewness(utility::VectorBase&), which uses an unbiased variance estimate [1/(n-1)] and may thus give different results for small n.
double theplu::yat::statistics::averager_base2< Averager4 >::standard_error ( void  ) const
inlineinherited
  \return Standard error, i.e. standard deviation of the mean

$ \sqrt{variance()/n} $

double theplu::yat::statistics::averager_base2< Averager4 >::std ( void  ) const
inlineinherited

The standard deviation is defined as the square root of the variance.

Returns:
The standard deviation, root of the variance().
double theplu::yat::statistics::averager_base2< Averager4 >::std ( double  m) const
inlineinherited

The standard deviation is defined as the square root of the variance.

Returns:
Standard deviation around m, root of the variance(m).
double theplu::yat::statistics::averager_base< Averager4 >::sum_x ( void  ) const
inlineinherited
Returns:
The sum of data values
double theplu::yat::statistics::averager_base3< Averager4 >::sum_x3_centered ( void  ) const
inlineinherited
  \return sum cubed centered

$ \sum (x_i-m)^3 $

double theplu::yat::statistics::averager_base4< Averager4 >::sum_x4_centered ( void  ) const
inlineinherited

sum quadrupled centered

Calculated as $ \frac{1}{n} \sum (x_i-m)^4 $

double theplu::yat::statistics::averager_base2< Averager4 >::sum_xx ( void  ) const
inlineinherited
Returns:
The sum of squares
double theplu::yat::statistics::averager_base2< Averager4 >::sum_xx_centered ( void  ) const
inlineinherited
Returns:
$ \sum_i (x_i-m)^2 $
double theplu::yat::statistics::averager_base2< Averager4 >::variance ( double  m) const
inlineinherited

The variance with known mean.

  The variance is calculated as

$ \frac{1}{n}\sum (x_i-m)^2 $.

  \return Variance when the mean is known to be \a m.
double theplu::yat::statistics::averager_base2< Averager4 >::variance ( void  ) const
inlineinherited

The estimated variance.

The variance is calculated as $ \frac{1}{N}\sum_i (x_i-m)^2 $, where $ m $ is the mean.

Returns:
Estimation of variance
double theplu::yat::statistics::averager_base2< Averager4 >::variance_unbiased ( void  ) const
inlineinherited
  The variance is calculated using the \form#230 correction,
  which means it is the best unbiased estimator of the variance

$ \frac{1}{N-1}\sum_i (x_i-m)^2 $, where $ m $ is the mean.

Returns:
unbiased estimation of variance

Member Data Documentation

double theplu::yat::statistics::averager_base2< Averager4 >::cm2_
protectedinherited

sum of values squared values centralized $ \sum (x-m)^2 $

double theplu::yat::statistics::averager_base3< Averager4 >::cm3_
protectedinherited

sum cubed centered

long int theplu::yat::statistics::averager_base< Averager4 >::n_
protectedinherited

number of data points


The documentation for this class was generated from the following file:

Generated on Mon Nov 11 2013 09:41:45 for yat by  doxygen 1.8.1