Parameter Inference and Optimal Designs for Grouped and/or Right-Censored Count Data R package GRCdata version 1.0 We implement two main functions. The first function uses a given grouped and/or right-censored grouping scheme and empirical data to infer parameters, and implements chi-square goodness-of-fit tests. The second function searches for the global optimal grouping scheme of grouped and/or right-censored count responses in surveys. Software Depends: nloptr, cubature Xin Guo <x.guo@polyu.edu.hk> Comprehensive R Archive Network (CRAN) Xin Guo <x.guo@polyu.edu.hk>, Qiang Fu <qiang.fu@ubc.ca> GPL (>= 3) 2017-08-20 application/tgz https://CRAN.R-project.org/package=GRCdata doi:10.32614/CRAN.package.GRCdata