Hello All, I am learning mixed effects logistic regression (lmer in lme4), and I am having problems deciphering the goodness of fit function plot.logistic.fit.fnc (languageR package). The only information I can find is that this function plots observed proportions against mean predicted probabilities for some binning of the data.
I have explored this function with several datasets, and have had some problems. The resultant plots (for example from the bacteria dataset in MASS) don't seem to match the predicted probabilities. For example, a given dataset will have a maximum predicted probability of 0.7, but the plot will show a point at 0.88. I have one dataset in which the "cut" method results in negative observed proportions. So, I'm not sure that I really understand how these mean predicted probabilities are calculated. Can somebody please explain this or suggest a reference? Thank you, Leslie [[alternative HTML version deleted]] ______________________________________________ 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.