手法を比較

	Manifest Content Analysis	Krippendorff's Alpha
分野	Communication	Communication
系統	Process / pipeline	Process / pipeline
提唱年	1952	1970
提唱者	Bernard Berelson; codified by Klaus Krippendorff	Klaus Krippendorff
種類	Systematic quantitative coding of explicit message content	Chance-corrected reliability coefficient for coded data
原典	Krippendorff, K. (2004). Content Analysis: An Introduction to Its Methodology (2nd ed.). Thousand Oaks, CA: Sage. ISBN: 9780761915454	Hayes, A. F., & Krippendorff, K. (2007). Answering the call for a standard reliability measure for coding data. Communication Methods and Measures, 1(1), 77–89.
別名	Quantitative manifest coding, Surface-content analysis, Manifest-level content analysis, Berelson content analysis	Krippendorff alpha, K-alpha, Alpha reliability coefficient, Krippendorff Alfa Katsayısı
関連	5	4
概要	Manifest content analysis is a quantitative research technique that systematically counts the explicit, surface-level features of communication messages — words, sources, themes, images, or actors that are directly visible in the text or media artifact — according to a predefined coding scheme. Rooted in Bernard Berelson's classic definition of content analysis as the 'objective, systematic, and quantitative description of the manifest content of communication,' it is one of the foundational empirical methods of mass communication and media research.	Krippendorff's alpha is a chance-corrected coefficient that quantifies the reliability of coding decisions made by two or more observers, and is the standard reliability statistic in communication content analysis. Unlike percent agreement, it corrects for the agreement expected by chance; unlike Cohen's kappa, it generalizes seamlessly to any number of coders, any measurement level (nominal, ordinal, interval, ratio), and data sets with missing values.