This is to announce the new R-package ‘ordinal’ that implements cumulative link (mixed) models for ordinal (ordered categorical) data (http://www.cran.r-project.org/package=ordinal/).
The main features are: - scale (multiplicative) as well as location (additive) effects - nominal effects for a subset of the predictors (denoted partial proportional odds when the link is the logistic) - structured thresholds, e.g. assuming symmetry or equidistant thresholds - random effects via the Laplace approximation and adaptive Gauss-Hermite quadrature in the location-part of the model. - a range of standard link functions - flexible link functions where an extra link function-parameter bridges the log-log, probit and c-loglog links (log-gamma), and cloglog and logistic links (Aranda-Ordaz) - a suite of optimizers including an efficient Newton scheme. - works for binomial observations (a special case of ordinal data). - a suite of methods including anova, addterm, dropterm, profile, confint, plot.profile, predict, in addition to the standard print and summary methods. - an important special case is the proportional odds model (with random effects). - a range of examples illustrates how to use the functions. Future additions will include: - more general random effect structures: multiple (crossed and nested) and vector-valued random effects. - profile methods for variance parameters in mixed effect models. - helpful package vignettes. - implementation of core functions in C. Comments, critique, suggestions, wishes and contributions are always highly appreciated. Kind regards Rune -- Rune Haubo Bojesen Christensen PhD student, M.Sc. Eng. Phone: (+45) 45 25 33 63 Mail: rhbc at imm.dtu.dk DTU Informatics, Section for Statistics Technical University of Denmark, Build. 305, Room 122, DK-2800 Kgs. Lyngby, Denmark _______________________________________________ R-packages mailing list r-packa...@r-project.org https://stat.ethz.ch/mailman/listinfo/r-packages ______________________________________________ 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.
