PLN_RE                  A Poisson Lognormal Model with Random Effects
PanelCount              Panel Count Models with Random Effects and/or
                        Sample Selection
PoissonRE               A Poisson Model with Random Effects
ProbitRE                A Probit Model with Random Effects
ProbitRE_PLNRE          Poisson Lognormal Model with Random Effects and
                        Sample Selection
ProbitRE_PoissonRE      Poisson RE model with Sample Selection
predict_ProbitRE_PLNRE
                        Predictions of ProbitRE_PLNRE model on new
                        sample
predict_ProbitRE_PoissonRE
                        Predictions of ProbitRE_PoissonRE model on new
                        sample
sim                     Simulated dataset with self-selection at both
                        individual and individual-time level
