A function for computing a 2x2 subset of original data. This is the subset with post treatment periods separately for the treated group and comparison group and pre-treatment periods in the period immediately before the treated group became treated.
Usage
two_by_two_subset(
data,
g,
tp,
control_group = "notyettreated",
anticipation = 0,
base_period = "varying",
...
)Arguments
- data
the full dataset
- g
the current group
- tp
the current time period
- control_group
whether to use "notyettreated" (default) or "nevertreated"
- anticipation
the number of periods of anticipation (i.e., number of periods before the treatment happens where the treatment can "already" affect the outcome)
- base_period
The type of base period to use. This only affects the numeric value of results in pre-treatment periods. Results in post-treatment periods are not affected by this choice. The default is "varying", where the base period will "back up" to the immediately preceding period in pre-treatment periods. The other option is "universal" where the base period is fixed in pre-treatment periods to be the period right before the treatment starts. "Universal" is commonly used in difference-in-differences applications, but can be unnatural for other identification strategies.
- ...
extra arguments to get the subset correct