com.datumbox.framework.core.statistics.sampling

Class SimpleRandomSampling

java.lang.Object

com.datumbox.framework.core.statistics.sampling.SimpleRandomSampling

public class SimpleRandomSampling
extends java.lang.Object

This class provides methods which can be used for performing Simple Random Sampling.

Constructor Summary

Constructors

Constructor and Description
SimpleRandomSampling()

Method Summary

Modifier and Type	Method and Description
static double	mean(FlatDataCollection flatDataCollection) Calculate the mean from the sample
static int	minimumSampleSizeForGivenDandMaximumRisk(double d, double aLevel, double populationStd) Returns the minimum required sample size when we set a predifined limit d and a maximum probability Risk a for infinite population size
static int	minimumSampleSizeForGivenDandMaximumRisk(double d, double aLevel, double populationStd, int populationN) Returns the minimum required sample size when we set a predefined limit d and a maximum probability Risk a for finite population size
static int	minimumSampleSizeForMaximumXbarStd(double maximumXbarStd, double populationStd) Returns the minimum required sample size when we set a specific maximum Xbar STD Error for infinite population size.
static int	minimumSampleSizeForMaximumXbarStd(double maximumXbarStd, double populationStd, int populationN) Returns the minimum required sample size when we set a specific maximum Xbar STD Error for finite population size.
static double	pbarStd(double pbar, int sampleN) Calculates Standard Deviation for Pbar for infinite population size
static double	pbarStd(double pbar, int sampleN, int populationN) Calculates Standard Deviation for Pbar for finite population size
static double	pbarVariance(double pbar, int sampleN) Calculates Variance for Pbar for infinite population size
static double	pbarVariance(double pbar, int sampleN, int populationN) Calculates Variance for Pbar for a finite population size
static FlatDataCollection	randomSampling(FlatDataList idList, int n, boolean withReplacement) Samples n ids by using SimpleRandomSampling (Simple Random Sampling).
static double	std(FlatDataCollection flatDataCollection) Calculate the standard deviation of the sample
static double	variance(FlatDataCollection flatDataCollection) Calculate the variance from the sample
static FlatDataCollection	weightedSampling(AssociativeArray weightedTable, int n, boolean withReplacement) Samples n ids based on their a Table which contains weights, probabilities or frequencies.
static double	xbarStd(double std, int sampleN) Calculates Standard Deviation for Xbar for infinite population size
static double	xbarStd(double std, int sampleN, int populationN) Calculates Standard Deviation for Xbar for finite population size
static double	xbarVariance(double variance, int sampleN) Calculates Variance for Xbar for infinite population size
static double	xbarVariance(double variance, int sampleN, int populationN) Calculates Variance for Xbar for a finite population size

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SimpleRandomSampling

public SimpleRandomSampling()

Method Detail

weightedSampling

public static FlatDataCollection weightedSampling(AssociativeArray weightedTable,
                                                  int n,
                                                  boolean withReplacement)

Samples n ids based on their a Table which contains weights, probabilities or frequencies.

Parameters:

weightedTable -

n -

withReplacement -

Returns:

randomSampling

public static FlatDataCollection randomSampling(FlatDataList idList,
                                                int n,
                                                boolean withReplacement)

Samples n ids by using SimpleRandomSampling (Simple Random Sampling).

Parameters:

idList -

n -

withReplacement -

Returns:

mean

public static double mean(FlatDataCollection flatDataCollection)

Calculate the mean from the sample

Parameters:

flatDataCollection -

Returns:

variance

public static double variance(FlatDataCollection flatDataCollection)

Calculate the variance from the sample

Parameters:

flatDataCollection -

Returns:

std

public static double std(FlatDataCollection flatDataCollection)

Calculate the standard deviation of the sample

Parameters:

flatDataCollection -

Returns:

xbarVariance

public static double xbarVariance(double variance,
                                  int sampleN)

Calculates Variance for Xbar for infinite population size

Parameters:

variance -

sampleN -

Returns:

xbarVariance

public static double xbarVariance(double variance,
                                  int sampleN,
                                  int populationN)

Calculates Variance for Xbar for a finite population size

Parameters:

variance -

sampleN -

populationN -

Returns:

xbarStd

public static double xbarStd(double std,
                             int sampleN)

Calculates Standard Deviation for Xbar for infinite population size

Parameters:

std -

sampleN -

Returns:

xbarStd

public static double xbarStd(double std,
                             int sampleN,
                             int populationN)

Calculates Standard Deviation for Xbar for finite population size

Parameters:

std -

sampleN -

populationN -

Returns:

pbarVariance

public static double pbarVariance(double pbar,
                                  int sampleN)

Calculates Variance for Pbar for infinite population size

Parameters:

pbar -

sampleN -

Returns:

pbarVariance

public static double pbarVariance(double pbar,
                                  int sampleN,
                                  int populationN)

Calculates Variance for Pbar for a finite population size

Parameters:

pbar -

sampleN -

populationN -

Returns:

pbarStd

public static double pbarStd(double pbar,
                             int sampleN)

Calculates Standard Deviation for Pbar for infinite population size

Parameters:

pbar -

sampleN -

Returns:

pbarStd

public static double pbarStd(double pbar,
                             int sampleN,
                             int populationN)

Calculates Standard Deviation for Pbar for finite population size

Parameters:

pbar -

sampleN -

populationN -

Returns:

minimumSampleSizeForMaximumXbarStd

public static int minimumSampleSizeForMaximumXbarStd(double maximumXbarStd,
                                                     double populationStd)

Returns the minimum required sample size when we set a specific maximum Xbar STD Error for infinite population size.

Parameters:

maximumXbarStd -

populationStd -

Returns:

minimumSampleSizeForMaximumXbarStd

public static int minimumSampleSizeForMaximumXbarStd(double maximumXbarStd,
                                                     double populationStd,
                                                     int populationN)

Returns the minimum required sample size when we set a specific maximum Xbar STD Error for finite population size.

Parameters:

maximumXbarStd -

populationStd -

populationN -

Returns:

minimumSampleSizeForGivenDandMaximumRisk

public static int minimumSampleSizeForGivenDandMaximumRisk(double d,
                                                           double aLevel,
                                                           double populationStd)

Returns the minimum required sample size when we set a predifined limit d and a maximum probability Risk a for infinite population size

Parameters:

d -

aLevel -

populationStd -

Returns:

minimumSampleSizeForGivenDandMaximumRisk

public static int minimumSampleSizeForGivenDandMaximumRisk(double d,
                                                           double aLevel,
                                                           double populationStd,
                                                           int populationN)

Returns the minimum required sample size when we set a predefined limit d and a maximum probability Risk a for finite population size

Parameters:

d -

aLevel -

populationStd -

populationN -

Returns: