(This article was first published on simon jackman's blog » R, and kindly contributed to R-bloggers)
Update to my pscl package, now on CRAN.
Biggest change: fixing a bug in the way MCMC draws for item parameters were being stored and summarized by ideal.
To leave a comment for the author, please follow the link and comment on his blog: simon jackman's blog » R.
R-bloggers.com offers daily e-mail updates about R news and tutorials on topics such as: visualization (ggplot2, Boxplots, maps, animation), programming (RStudio, Sweave, LaTeX, SQL, Eclipse, git, hadoop, Web Scraping) statistics (regression, PCA, time series, trading) and more...

Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).