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Glossary

Factor analysis

A family of statistical methods for identifying the underlying latent factors that explain correlations among observed items.

Factor analysis is a family of statistical methods used to identify the underlying ("latent") factors that explain patterns of correlations among observed variables. In assessment, it's used to discover how many distinct constructs an item set is really measuring — and which items belong to each one.

Exploratory factor analysis (EFA) is used when researchers don't have a strong prior structure in mind: the method finds the factors that best account for the correlations. Confirmatory factor analysis (CFA) tests a specific predicted structure: "Do these 12 items form three subscales as theorized?" CFA model fit indices are standard fare in modern assessment validation papers.