mgcv(>= 1.8-12), glm2(>= 1.1.2), nlme(>= 3.1-128), survival(>=
2.40-1), MASS, arm, lme4, twang, gbm, lattice, splines,
parallel, survey, grid, Matrix, xtable, latticeExtra,
RColorBrewer, epiDisplay, foreign, nnet