Changes in version 1.0.7                        

  - Extended double DiD to support M>2 treatment events: cohortvar2 now
    accepts a character vector of length M-1 (e.g. c("G2", "G3") for
    three events)
  - Added add_base_period parameter: inserts a zero-ATT placeholder at
    the base period in result_type = "dynamic" results
  - Added experimental options only_est_min and only_est_max in exper:
    restrict estimation to a specific event-time range in dynamic mode,
    skipping g-t pairs outside the window
  - Improved input validation: errors on negative
    anticipation/anticipation2, time-varying weights, and
    balanced_event_time exceeding data range
  - Restored parglm dependency for multi-threaded propensity score
    estimation; thread count automatically matched to getDTthreads()
    (or 1 when parallel = TRUE)
  - Various bug fixes and robustness improvements for double DiD
    aggregation and weight handling

                 Changes in version 1.0.6 (2026-01-14)                  

  - Remove archived parglm dependency

                 Changes in version 1.0.5 (2025-06-23)                  

  - Various bug fixes

                        Changes in version 1.0.4                        

  - Fixed Double DiD inference: account for stolastic part of the double
    DiD weight

                 Changes in version 1.0.3 (2024-11-04)                  

  - Fixed Check for CRAN

                 Changes in version 1.0.2 (2024-10-28)                  

  - Fixed Typo for CRAN

                        Changes in version 1.0.1                        

  - Fixed Typo for CRAN

                        Changes in version 1.0.0                        

  - Release to CRAN!

                        Changes in version 0.9.9                        

  - add double did (see the vignette for the introduction)
  - add parallel, parallization for unix systems, useful if the number
    of g-t is large.
  - add full, return full result such as influence function, aggregate
    scheme, and such
  - add min/max_dynamic, custom_scheme to experimental features

0.9.9.1 (2024/9/13): fix a bug that affects not-yet control with max
treated group != max time

                        Changes in version 0.9.4                        

Some BREAKING change is introduced in this update.

  - add uniform confidence interval option with cband and significance
    level alpha, confidence interval are now provided in result as
    column att_ciub and att_cilb
  - BREAKING: filtervar, max_control_cohort_diff,
    min_control_cohort_diff are moved into the experimental features.
    See the above section for the explanation.
  - add max_dynamic and min_dynamic as experimental features.
  - more informative error message when estimation fails for a specific
    gt, some internal interface overhaul

                        Changes in version 0.9.3                        

  - add anticipation and varying base period option
  - add min and max control cohort difference
  - add time-varying control (reference)
  - add filtervar

0.9.3.1 (2024/5/24): fix the bug with univar == clustervar (TODO:
address problems with name-changing and collision). 0.9.3.2 (2024/7/17):
fix group_time result when using control_type = "notyet" and make the
base period in plots adapt to anticipation. 0.9.3.3 (2024/7/22): fix
anticipation out of bound problem, more permanent solution for
group_time target problem

                        Changes in version 0.9.2                        

  - add support to doubly robust and outcome regression estimators
  - add support to unbalanced panels (simple and ipw only)
  - add support to balanced composition option in dynamics aggregation
  - fixed argument checking that was not working properly
  - set the default to copying the entire dataset to avoid unexpected
    modification of the original data (thanks @grantmcdermott for the
    suggestion.)

                        Changes in version 0.9.1                        

  - now supprts estimation for multiple outcomes in one go!
  - data validation: no longer check missing values for columns not
    used.