Dundas Chart for Windows Forms
TTestPaired Method
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DundasWinChart Assembly > Dundas.Charting.WinControl Namespace > Statistics Class : TTestPaired Method


hypothesizedMeanDifference
The hypothesized difference between the means of the data groups.
Hypothesized Mean Difference
probability
The alpha value (probability that the hypothesis is rejected).
Probability
firstInputSeriesName
The name of the Series object that stores the first group of data. Data must be stored in the first Y-values of the series' data points.
First Input Series Name
secondInputSeriesName
The name of the Series object  that stores the second group of data. Data must be stored in the first Y-values of the series' data points.
Second Input Series Name

Enterprise Edition Only Feature. This method performs a T Test using Students distribution (T distribution) with paired samples.


This analysis tool and its formula perform a paired two-sample student's t-test to determine whether a sample's means are distinct. This t-test form does not assume that the variances of both populations are equal. You can use a paired test when there is a natural pairing of observations in the samples, such as when a sample group is tested twice — before and after an experiment.

Syntax

Visual Basic (Declaration)  
Public Function TTestPaired( _
   ByVal hypothesizedMeanDifference As Double, _
   ByVal probability As Double, _
   ByVal firstInputSeriesName As String, _
   ByVal secondInputSeriesName As String _
) As TTestResult
Visual Basic (Usage) Copy Code
Dim instance As Statistics
Dim hypothesizedMeanDifference As Double
Dim probability As Double
Dim firstInputSeriesName As String
Dim secondInputSeriesName As String
Dim value As TTestResult
 
value = instance.TTestPaired(hypothesizedMeanDifference, probability, firstInputSeriesName, secondInputSeriesName)

Parameters

hypothesizedMeanDifference
The hypothesized difference between the means of the data groups.
Hypothesized Mean Difference
probability
The alpha value (probability that the hypothesis is rejected).
Probability
firstInputSeriesName
The name of the Series object that stores the first group of data. Data must be stored in the first Y-values of the series' data points.
First Input Series Name
secondInputSeriesName
The name of the Series object  that stores the second group of data. Data must be stored in the first Y-values of the series' data points.
Second Input Series Name

Return Value

Returns Result class from T Test

Example

The following sample performs a t test with paired samples, represented by Series1 and Series2. The results are returned in a TTestResult object.
Visual Basic Copy Code
Imports Dundas.Charting.WinControl
...

' Perform the test
Dim result As TTestResult = Chart1.DataManipulator.Statistics.TTestPaired(0.2,0.05,"Series1","Series2")
C# Copy Code
using Dundas.Charting.WinControl;
...

// Perform the testT
TestResult result = Chart1.DataManipulator.Statistics.TTestPaired(0.2,0.05,"Series1","Series2");

Remarks

This method performs a paired two-sample student's t-test to determine whether a sample's means are distinct. This form of the t-test does not assume that the variances of both populations are equal.

Use a paired test when there is a natural pairing of observations in the samples, such as a sample group that is tested twice (e.g. before and after an experiment).

If either input series does not exist in the series collection at the time of the method call an exception will be thrown.

The following is a brief description of the TTestResult class members:

Member Description
FirstSeriesMean  The mean of the first data group.
SecondSeriesMean  The mean of the second data group.
FirstSeriesVariance  The variance of the first data group.
SecondSeriesVariance  The variance of the second data group. 
TValue  The T value.
DegreeOfFreedom  The degree of freedom.
ProbabilityTOneTail  Probability - T value (one tail).
TCriticalValueOneTail  T critical value (one tail).
ProbabilityTTwoTail   Probability - T value (two tail).
TCriticalValueTwoTail  T critical value (two tail).

Requirements

Target Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, Windows Vista, Windows Server 2008 family

See Also

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