Libraries.Compute.Statistics.Tests.CompareDistributions Documentation

This class implements two tests: CompareDistributionToNormal is a Shapiro-Wilk Test Check if a sample is distributed normally For more information: https://en.wikipedia.org/wiki/Shapiro%E2%80%93Wilk_test ________________ is a Kolmogorov-Smirnov Test Check a sample's distribution against a known distribution For more information: https://en.wikipedia.org/wiki/Kolmogorov%E2%80%93Smirnov_test It was partially adapted from a similar model in Apache Commons, and FORTAN but was expanded upon to simplify the library and add a variety of helper actions and calculations that were missing. More information about this class can be found on then documentation pages KolmogorovSmirnovTest: https://commons.apache.org/proper/commons-math/javadocs/api-3.6.1/index.html FORTRAN: http://lib.stat.cmu.edu/apstat/R94

Example Code

use Libraries.Compute.Statistics.DataFrame
use Libraries.Compute.Statistics.Tests.CompareDistributions

DataFrame frame
frame:Load("Data/Data.csv")

CompareDistributions compare
compare:AddColumn(0)
frame:Calculate(compare)
output frame:GetFormalSummary()

Inherits from: Libraries.Compute.Statistics.DataFrameCalculation, Libraries.Compute.Statistics.Tests.StatisticalTest, Libraries.Language.Object, Libraries.Compute.Statistics.Inputs.ColumnInput, Libraries.Compute.Statistics.Inputs.FactorInput

Actions Documentation

AddColumn(integer column)

This action adds a value to the end of the input.

Parameters

  • integer column

AddFactor(integer column)

This action adds a value to the end of the input.

Parameters

  • integer column

Calculate(Libraries.Compute.Statistics.DataFrame frame)

Compare(Libraries.Language.Object object)

This action compares two object hash codes and returns an integer. The result is larger if this hash code is larger than the object passed as a parameter, smaller, or equal. In this case, -1 means smaller, 0 means equal, and 1 means larger. This action was changed in Quorum 7 to return an integer, instead of a CompareResult object, because the previous implementation was causing efficiency issues.

Parameters

Return

integer: The Compare result, Smaller, Equal, or Larger.

Example

Object o
Object t
integer result = o:Compare(t) //1 (larger), 0 (equal), or -1 (smaller)

CompareDistributionToNormal(Libraries.Compute.Statistics.DataFrame frame)

Shapiro-Wilk Test tests for normality on each sample Null hypothesis: The sample MAY be normally distributed Alternative hypothesis: The sample is not normally distributed.

Parameters

Example


    use Libraries.Compute.Statistics.DataFrame
    use Libraries.Compute.Statistics.Tests.CompareDistributions

    DataFrame frame
    frame:Load("data.csv")

    CompareDistributions compare 
    compare:AddColumn(0)
    compare:AddColumn(1)
    compare:AddColumn(2)
    compare:Calculate(frame)

    output compare:GetFormalSummary()

EmptyColumns()

This action empty's the list, clearing out all of the items contained within it.

EmptyFactors()

This action empty's the list, clearing out all of the items contained within it.

Equals(Libraries.Language.Object object)

This action determines if two objects are equal based on their hash code values.

Parameters

Return

boolean: True if the hash codes are equal and false if they are not equal.

Example

use Libraries.Language.Object
use Libraries.Language.Types.Text
Object o
Text t
boolean result = o:Equals(t)

GetColumn(integer index)

This action gets the item at a given location in an array.

Parameters

  • integer index

Return

integer: The item at the given location.

GetColumnIterator()

This action gets an iterator for the object and returns that iterator.

Return

Libraries.Containers.Iterator: Returns the iterator for an object.

GetColumnSize()

This action gets the size of the array.

Return

integer:

GetDegreesOfFreedom()

This returns the degrees of freedom if only one result exists.

Return

number: the Degrees of Freedom.

GetFactor(integer index)

This action gets the item at a given location in an array.

Parameters

  • integer index

Return

integer: The item at the given location.

GetFactorIterator()

This action gets an iterator for the object and returns that iterator.

Return

Libraries.Containers.Iterator: Returns the iterator for an object.

GetFactorSize()

This action gets the size of the array.

Return

integer:

GetFactorText()

Return

text

GetFormalSummary()

This action summarizes the results and places them into formal academic language, in APA format. For more information: https://apastyle.apa.org/instructional-aids/numbers-statistics-guide.pdf

Return

text: a condensed formal result of the test

Example

use Libraries.Compute.Statistics.DataFrame
use Libraries.Compute.Statistics.Tests.CompareDistributions
    
DataFrame frame
frame:Load("Data/Data.csv")
    
CompareDistributions compare
compare:Add(0)
compare:Add(1)
frame:Calculate(compare)

output compare:GetFormalSummary()

GetGroups(Libraries.Compute.Statistics.DataFrame frame)

Gets the the fully factored samples/groups in an array of dataframes. Using an array of dataframes instead of a single dataframe helps with multivariate cases.

Parameters

Return

Libraries.Containers.HashTable:

GetHashCode()

This action gets the hash code for an object.

Return

integer: The integer hash code of the object.

Example

Object o
integer hash = o:GetHashCode()

GetProbabilityValue()

This returns the probability if only one result exists.

Return

number: the P-Value.

GetResult()

This returns a result if only one exists.

Return

Libraries.Compute.Statistics.Reporting.CompareDistributionsResult: the CompareDistributionsResult object

Example

use Libraries.Compute.Statistics.DataFrame
use Libraries.Compute.Statistics.Tests.CompareDistributions
    
DataFrame frame
frame:Load("Data/Data.csv")

CompareVariances compare
compare:AddColumn(0)
compare:AddColumn(1)
compare:Calculate(frame)

CompareDistributions result = compare:GetResult()

GetResults()

Return

Libraries.Containers.Array: an array of CompareDistributionsResult objects

Example

use Libraries.Compute.Statistics.DataFrame
use Libraries.Compute.Statistics.Tests.CompareDistributions
    
DataFrame frame
frame:Load("Data/Data.csv")
    
CompareDistributions compare
compare:AddColumn(0)
compare:AddColumn(1)
compare:AddColumn(2)
frame:Calculate(compare)

Array<CompareDistributionsResult> results = compare:GetResults()

GetSignificanceLevel()

A list of unique items of the factor

Return

number:

GetStatisticalFormatting()

GetSummary()

Return

text: a list of the important statistics of the test

Example

use Libraries.Compute.Statistics.DataFrame
use Libraries.Compute.Statistics.Tests.CompareDistributions
    
DataFrame frame
frame:Load("Data/Data.csv")
    
CompareDistributions compare
compare:Add(0)
compare:Add(1)
frame:Calculate(compare)

output compare:GetSummary()

GetSummaryDataFrame()

Return

Libraries.Compute.Statistics.DataFrame: a DataFrame of the important statistics of the test

Example

use Libraries.Compute.Statistics.DataFrame
use Libraries.Compute.Statistics.Tests.CompareDistributions
    
DataFrame frame
frame:Load("Data/Data.csv")
    
CompareDistributions compare
compare:Add(0)
compare:Add(1)
frame:Calculate(compare)

DataFrame result = compare:GetSummaryDataFrame()
result:Save("myresult.csv")

GetTestStatistic()

This returns the test statistic if only one result exists.

Return

number: the test statistic.

IsEmptyColumns()

This action returns a boolean value, true if the container is empty and false if it contains any items.

Return

boolean: Returns true when the container is empty and false when it is not.

IsEmptyFactors()

This action returns a boolean value, true if the container is empty and false if it contains any items.

Return

boolean: Returns true when the container is empty and false when it is not.

RemoveColumn(integer column)

This action removes the first occurrence of an item that is found in the Addable object.

Parameters

  • integer column

Return

boolean: Returns true if the item was removed and false if it was not removed.

RemoveColumnAt(integer index)

This action removes an item from an indexed object and returns that item.

Parameters

  • integer index

RemoveFactor(integer column)

This action removes the first occurrence of an item that is found in the Addable object.

Parameters

  • integer column

Return

boolean: Returns true if the item was removed and false if it was not removed.

RemoveFactorAt(integer index)

This action removes an item from an indexed object and returns that item.

Parameters

  • integer index

SetSignificanceLevel(number significanceLevel)

Sets the significance level of the test (default is 0.05).

Parameters

  • number significanceLevel: the significance level between 0 and 1.

SetStatisticalFormatting(Libraries.Compute.Statistics.Reporting.StatisticsFormatting formatting)

Create a new frame based on that list

Parameters

UseFactor()

Return

boolean