com.itemanalysis.psychometrics.irt.equating

Class IrtTrueScoreEquating

java.lang.Object

com.itemanalysis.psychometrics.irt.equating.IrtTrueScoreEquating

public class IrtTrueScoreEquating
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
IrtTrueScoreEquating(java.util.LinkedHashMap<java.lang.String,ItemResponseModel> itemFormX, java.util.LinkedHashMap<java.lang.String,ItemResponseModel> itemFormY)

Method Summary

Modifier and Type	Method and Description
void	equateScores() Primary method for conducting the IRT true score equating.
double[]	getFormXThetaValues()
double[]	getScorePoints() Score points at which y equivalent is sought
char[]	getStatus() Newton-Rhapson convergence status
double[]	getYEquivalentTrueScores()
java.lang.String	printResults() Display results in text format with this method.
double	xTrueScoreToTheta(double trueScore) Find Form X theta values that corresponds to a particular true score.

Methods inherited from class java.lang.Object

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

Constructor Detail

IrtTrueScoreEquating

public IrtTrueScoreEquating(java.util.LinkedHashMap<java.lang.String,ItemResponseModel> itemFormX,
                            java.util.LinkedHashMap<java.lang.String,ItemResponseModel> itemFormY)

Method Detail

xTrueScoreToTheta

public double xTrueScoreToTheta(double trueScore)

Find Form X theta values that corresponds to a particular true score. This method uses a Newton-Rhapson procedure to find the theta value.

Parameters:

trueScore - value for which form X theta is sought

Returns:

equateScores

public void equateScores()

Primary method for conducting the IRT true score equating.

getScorePoints

public double[] getScorePoints()

Score points at which y equivalent is sought

Returns:

getFormXThetaValues

public double[] getFormXThetaValues()

Returns:

Form X theta values that correspond to raw scores.

getYEquivalentTrueScores

public double[] getYEquivalentTrueScores()

Returns:

Form X true scores that are equivalent to Form Y true scores.

getStatus

public char[] getStatus()

Newton-Rhapson convergence status

Returns:

printResults

public java.lang.String printResults()

Display results in text format with this method.

Returns: