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bggum provides an implementation for the Generalized Graded Unfolding Model (GGUM) of Roberts, Donoghue, and Laughlin (2000) for R. Rather than provide tools for marginal maximum likelihood estimation, which is available from the package GGUM currently available on CRAN, we provide an implementation of the MCMC algorithm in de la Torre et al (2006) as well as a Metropolis-coupled MCMC algorithm, both coded in C++ to allow for reasonable execution time using Rcpp (and using probability distribution functions written in C++ from RcppDist).


bggum is not yet on CRAN. You can install the development version from GitHub via



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GPL (>= 2)