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Ordinary Least Squares Estimation of Parameters in Exploratory Factor Analysis With Ordinal Data
Chun-Ting Lee1, Guangjian Zhang1, Michael C Edwards2
1a University of Notre Dame.
Exploratory factor analysis (EFA) using polychoric correlations with ordinary least squares (OLS) is feasible for large models. OLS provides unbiased factor loading estimates and accurate confidence intervals for ordinal data analysis.
Area of Science:
- Social and behavioral sciences
- Psychometrics
- Statistical modeling
Background:
- Ordinal data, common in social sciences, is often inappropriately treated as continuous.
- Existing methods for exploratory factor analysis (EFA) with ordinal data have limitations.
Purpose of the Study:
- To propose and evaluate ordinary least squares (OLS) estimation for EFA using polychoric correlations.
- To provide standard errors and confidence intervals for parameter estimates in this context.
Main Methods:
- Estimation of polychoric correlations from ordinal data.
- Application of OLS to the EFA model specified on underlying continuous variables.
- Monte Carlo simulations to assess statistical properties.
- Empirical illustration with personality trait ratings.
Main Results:
- OLS estimation of EFA is feasible even for large models.
- Point estimates of rotated factor loadings are unbiased.
- Accurate standard errors and confidence intervals are provided.
Conclusions:
- The proposed OLS approach offers a viable method for EFA with ordinal data.
- This method enhances the analysis of complex psychological and social constructs.
- The findings support the use of OLS with polychoric correlations for robust EFA.
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