手法を比較

	一般化可能性理論（G理論）	クロンバックのα（信頼性分析）
分野	心理測定学	統計学
系統	Latent structure	Latent structure
提唱年	1963	1951
提唱者	Lee J. Cronbach and colleagues	Lee J. Cronbach
種類	ANOVA-based variance-component framework	Reliability / internal consistency coefficient
原典	Brennan, R. L. (2001). Generalizability Theory. Springer.	Cronbach, L. J. (1951). Coefficient alpha and the internal structure of tests. Psychometrika, 16(3), 297–334.
別名	Generalizability Theory, G-Study / D-Study framework, Genellenebilirlik Kuramı (G-Kuramı)	coefficient alpha, alpha reliability, internal consistency reliability, Güvenilirlik Analizi (Cronbach Alpha)
関連	6	4
概要	Generalizability Theory, developed by Lee J. Cronbach and colleagues in the 1960s and formalised by Brennan (2001), is an ANOVA-based framework that extends Classical Test Theory by decomposing observed score variance into multiple, separately identified sources of measurement error — such as raters, tasks, occasions, or items — rather than bundling all error into a single undifferentiated term.	Cronbach's alpha is a coefficient of internal consistency that quantifies the degree to which a set of items on a scale measures the same underlying construct. Introduced by Lee J. Cronbach in 1951, it remains the most widely reported reliability index in social-science, health, and educational research.