Added new aggregation methods for staggered adoption:
"sgt", "time", and "none".
"sgt" computes subaggregate ATTs for each
treatment-time and post-treatment period pair, further separated by
silo."time" computes subaggregate ATTs grouped by time since
treatment."none" skips subaggregate ATT computation and directly
computes the aggregate ATT from the underlying differences.undid_stage_three() now returns an object of class
UnDiDObj, providing a unified S3 interface.
print(), summary(),
coef(), and plot().Added support for event study plots via the plot()
method for UnDiDObj objects.
Added randomization inference p-values for subaggregate ATTs.
Fixed a miscalculation of jackknife standard errors and p-values.
Expanded weighting options for ATT computation:
"none", "diff", "att", and
"both".
"diff" applies weights when computing subaggregate
ATTs."att" applies weights when aggregating subaggregate
ATTs."both" applies weighting at both stages."none" disables weighting entirely.as.Date() calls in
undid_stage_two(), undid_stage_three(), and
plot_parllel_trends() to ensure compatability for R
versions 4.0.0 and onwards.