Cohen, J. (1960). A coefficient of agreement for nominal scales. Educational and Psychological Measurement, 20, 37-46.
Cohen, J. (1968). Weighted kappa: Nominal scale agreement with provision for scaled disagreement or partial credit. Psychological Bulletin, 70, 213-220. Francisco Dr. Francisco J. Zagmutt College of Veterinary Medicine and Biomedical Sciences Colorado State University Christian Schulz wrote: > Hi, > > im little bit confused about Cohen's Kappa and i should be look into the > Kappa function code. Is the easy formula really wrong? > > kappa=agreement-chance/(1-chance) > > many thanks > christian > > ############################################################################### > true-negativ:7445 > false-positive:3410 > false-negativ:347 > true-positiv:772 > > classification-aggrement:68,6% > kappa=agreement-chance/(1-chance) = (0.686-0.5)/0.5=0.372 > > ......with function from library(vcd) > Kappa(matrix(c(7445,3410,347,772),nrow=2)) > value ASE > Unweighted 0.1686882 0.011235188 > Weighted 0.1686882 0.007979293 > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.