elapsed                 Elapsed dates (monthly, quarterly)
fill_gap                Add rows corresponding to gaps in some variable
is.panel                Check whether a data.frame is a panel
join                    Join two data frames together
n_narm                  Count number of non missing observations
pctile                  Weighted quantile of type 2 (similar to Stata
                        _pctile)
stat_binmean            Plot the mean of y over the mean of x within
                        bins of x.
statar                  A package for applied research
sum_up                  Gives summary statistics (corresponds to Stata
                        command summarize)
tab                     Returns cross tabulation
tempname                Create unique names within a list, a
                        data.frame, or an environment
tlead-tlag              lead and lag with respect to a time variable
winsorize               Winsorize a numeric vector
xtile                   Bin variable in groups (similar to Stata xtile)
