手法を比較

	2母数ロジスティックIRTモデル（2PL）	評者間信頼性（コーエンのカッパおよびICC）
分野	心理測定学	心理測定学
系統	Latent structure	Latent structure
提唱年	1980	1960 (kappa); 1979 (ICC)
提唱者	Frederic M. Lord	Cohen (kappa, 1960); Shrout & Fleiss (ICC, 1979)
種類	Item response model / latent trait model	Reliability / agreement analysis
原典	Lord, F. M. (1980). Applications of Item Response Theory to Practical Testing Problems. Erlbaum.	Cohen, J. (1960). A Coefficient of Agreement for Nominal Scales. Educational and Psychological Measurement, 20(1), 37–46.
別名	two-parameter logistic model, 2PL model, 2PL IRT — İki Parametreli Madde Tepki Modeli	inter-rater reliability, interrater agreement, rater agreement, Değerlendiriciler Arası Güvenilirlik (Cohen's κ, ICC)
関連	6	6
概要	The two-parameter logistic item response model, formalised by Frederic Lord (1980), describes the probability that a respondent answers a binary test item correctly as a smooth S-shaped function of the respondent's latent ability. By estimating a separate discrimination parameter for each item alongside a difficulty parameter, 2PL allows items to differ in how sharply they distinguish high- from low-ability respondents — making it the standard model for large-scale educational and psychological assessments.	Interrater reliability quantifies the degree to which two or more independent raters produce consistent scores when evaluating the same individuals or products. The family encompasses Cohen's kappa, introduced in 1960 for categorical judgments, and the Intraclass Correlation Coefficient (ICC) for continuous ratings, together spanning most measurement scenarios encountered in behavioral, health, and educational research.