% correct is an improper scoring rule and a discontinuous one to boot. So it will not always agree with more proper scoring rules.
When you have a more difficult task, e.g., discriminating more categories, indexes such as the generalized c-index that utilize all the categories will recognize the difficulty of the task and give a lower value. No cause for alarm. Frank ----- Frank Harrell Department of Biostatistics, Vanderbilt University -- View this message in context: http://r.789695.n4.nabble.com/predict-lrm-Design-package-tp2546894p2550118.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org 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.
