Toolkit for Weighting and Analysis of Nonequivalent Groups This package offers functions for propensity score estimating and weighting, nonresponse weighting, and diagnosis of the weights. This package was originally developed by Drs. Ridgeway, McCaffrey, and Morral. Burgette, Griffin and McCaffrey updated the package in 2011. Software Depends: R (>= 2.10), gbm (>= 1.5-3), survey, xtable, latticeExtra Lane Burgette <burgette@rand.org> Greg Ridgeway <gregr@rand.org>, Dan McCaffrey <danielm@rand.org>, Andrew Morral <morral@rand.org>, Beth Ann Griffin <bethg@rand.org>, Lane Burgette <burgette@rand.org> GPL (>= 2) 2012-03-08 application/tgz http://CRAN.R-project.org/package=twang