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NAEP Analysis and Scaling → Estimation of NAEP Score Scales → NAEP Scales → Correlations Among NAEP Subject Area Subscales → Calculating Conditional Correlation Coefficients

NAEP Technical DocumentationCalculating Conditional Correlation Coefficients

Conditional correlation coefficients are estimates of the Pearson product-moment correlations between scores on the subscales within a content area. They can generally be thought of as partial correlations, but the model used to generate them is more complex than a simple regression model. The conditional correlation coefficients and residual variances are calculated by the conditioning program (Thomas 1994) and are estimates conditional on the set of principal components included in the models used to estimate group score distributions. Both conditional and marginal correlations are estimated from scales created using both IRT models for items and population models to account for subgroup membership.

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