CasesTable              Create reports cases after listwise deletion of
                        missing values for time-series cross-sectional
                        data.
CountSpell              Count spells, including for grouped data
DropNA                  Drop rows from a data frame with missing values
                        on a given variable(s).
FillDown                Fills in missing (NA) values with the previous
                        non-missing value
FillIn                  A function for filling in missing values of a
                        variable from one data frame with the values
                        from another variable.
FindDups                Find duplicated values in a data frame and
                        subset it to either include or not include
                        them.
FindReplace             Replace multiple patterns found in a character
                        string column of a data frame
InsertRow               Inserts a new row into a data frame
MoveFront               Move variables to the front of a data frame.
NaVar                   Create new variable(s) indicating if there are
                        missing values in other variable(s)
PercChange              Calculate the percentage change from a
                        specified lag, including within groups
SpreadDummy             Spread a dummy variable (1's and 0') over a
                        specified time period and for specified groups
StartEnd                Find the starting and ending time points of a
                        spell
TimeExpand              Expands a data set so that it includes an
                        observation for each time point in a sequence.
                        Works with grouped data.
TimeFill                Creates a continuous Unit-Time-Dummy data frame
                        from a data frame with Unit-Start-End times
VarDrop                 Drop one or more variables from a data frame.
change                  Calculate the changes (absolute, percent, and
                        proportion) changes from a specified lag,
                        including within groups
dMerge                  Merges 2 data frames and report/drop/keeps only
                        duplicates.
grepl.sub               Subset a data frame if a specified pattern is
                        found in a character string
rmExcept                Remove all objects from a workspace except
                        those specified by the user.
shift                   A function for creating lag and lead variables.
shiftMA                 Internal function for slideMA
slide                   A function for creating lag and lead variables,
                        including for time-series cross-sectional data.
slideMA                 Create a moving average for a period before or
                        after each time point for a given variable