Erratum to: PSYCHOMETRIKA 2012 DOI10.1007/s11336-012-9262-8
In Equation (19) of the paper, the denominator m should be deleted. In the BPSA-1 hybrid approach, we view the treatment effect estimate \documentclass[12pt]{minimal}
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\begin{document}$\hat{\gamma}$\end{document} as the posterior mean of γ based on the posterior distribution of propensity score model parameters rather than the frequentist-based mean of \documentclass[12pt]{minimal}
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as shown in Equations (14) and (15). We utilize the total variance formula to estimate the variance of \documentclass[12pt]{minimal}
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in BPSA-1. Then
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From Equation (16) to (18) with \documentclass[12pt]{minimal}
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\begin{document}$\hat{\gamma}_{1}$\end{document} replaced by \documentclass[12pt]{minimal}
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we obtain the corrected Equation (19)
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All the results presented in the tables are correct and based on this variance expression.