IRT studies of many groups: the alignment method

Bengt Muthã©N,Tihomir Asparouhov

doi:10.3389/fpsyg.2014.00978

Abstract

Asparouhov and Muthén (2014) presented a new method for multiple-group confirmatory factor analysis (CFA), referred to as the alignment method. The alignment method can be used to estimate group-specific factor means and variances without requiring exact measurement invariance. A strength of the method is the ability to conveniently estimate models for many groups, such as with comparisons of countries. This paper focuses on IRT applications of the alignment method. An empirical investigation is made of binary knowledge items administered in two separate surveys of a set of countries. A Monte Carlo study is presented that shows how the quality of the alignment can be assessed.

Highlights

Asparouhov and Muthén (2014) presented a new method for multiple-group confirmatory factor analysis (CFA), referred to as the alignment method
This paper focuses on item response theory (IRT) applications of the alignment method
Using item response theory (IRT) language, ag is the discrimination parameter and where p = 1, . . . , P and P is the number of observed indicator variables, g = 1, . . . , G and G is the number of groups, i = 1, . . . , Ng where Ng is the number of independent observations in group g, ηig is a latent variable and we assume that www.frontiersin.org

Summary

INTRODUCTION

Asparouhov and Muthén (2014) presented a new method for multiple-group confirmatory factor analysis (CFA), referred to as the alignment method. The alignment method can be used to estimate group-specific factor means and variances without requiring exact measurement invariance. The method is a valuable alternative to the currently used multiple-group CFA methods for studying measurement invariance that require multiple manual model adjustments guided by modification indices. The alignment method is based on the configural model and essentially automates and greatly simplifies measurement invariance analysis. The alignment method is based on the idea of starting from the configural model with no invariance and attempting to find as much invariance as possible by letting the factor means and variances vary across groups

THE ALIGNMENT METHOD

THE ALIGNMENT FITTING FUNCTION

AN ILLUSTRATION COMPARING COUNTRIES IN TWO CROSS-SECTIONAL SURVEYS

Findings

CONCLUSIONS