手法を比較

	Scott's Pi	Intercoder Reliability
分野	Communication	Communication
系統	Process / pipeline	Process / pipeline
提唱年	1955	1960
提唱者	William A. Scott	Foundational coefficients by Cohen (1960) and Krippendorff (1970)
種類	Chance-corrected agreement coefficient for two coders on nominal scales	Procedure and coefficients for certifying coding agreement
原典	Scott, W. A. (1955). Reliability of content analysis: The case of nominal scale coding. Public Opinion Quarterly, 19(3), 321–325.	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	Scott pi, Scott's index of reliability, Pi reliability coefficient, Scott Pi Katsayısı	Inter-rater reliability, Coder agreement assessment, Reliability of coding, Kodlayıcılar Arası Güvenirlik
関連	4	4
概要	Scott's pi is a chance-corrected coefficient of intercoder agreement for two coders working on a nominal scale, introduced by William Scott in 1955 specifically for content analysis. It improves on raw percent agreement by subtracting the agreement two coders would reach by chance, where chance is estimated from a single pooled distribution of categories shared by both coders rather than from each coder's separate marginals.	Intercoder reliability is the degree to which independent coders, applying the same coding scheme to the same content, arrive at the same coding decisions. In content analysis it is the central guarantee that findings reflect the messages rather than the idiosyncrasies of who happened to code them, and reporting a chance-corrected reliability coefficient is a near-universal requirement for publication in communication research.