Package: phdid
Title: Partial Homogeneity in Staggered Difference-in-Differences
Version: 0.1.0
Authors@R: c(
    person("Rohan", "Wagle", email = "rohan.wagle_ug2023@ashoka.edu.in",
           role = c("aut", "cre", "cph")),
    person("Parush", "Arora", email = "parush.arora@ashoka.edu.in",
           role = c("aut", "cph")))
Description: In staggered difference-in-differences designs the treatment
    effect is a vector of cohort-time effects rather than a single number.
    Estimating each separately is unbiased but imprecise when some are equal,
    while pooling them all is precise but biased under genuine heterogeneity.
    This package treats the choice as a partition-selection problem on the
    cohort-time cells and provides two estimators for it: a Dirichlet process
    mixture fitted by a collapsed Gibbs sampler, whose posterior marginalises
    over the unknown partition and reports co-clustering probabilities, and an
    'L0'-penalised estimator that returns a single partition and arises as the
    fixed-variance maximum a posteriori solution of the same model. Also
    provides tests for whether the cohort-time effects carry recoverable
    heterogeneity at all, sampler diagnostics including exact enumeration of
    the partition posterior for small designs, regularisation paths for both
    estimators, and a calibrated data-generating process. All estimators accept
    a vector of first-stage cohort-time effects with their joint covariance, so
    any heterogeneity-robust first-stage estimator may be used. Methods are
    described in Arora and Wagle (2026) <doi:10.2139/ssrn.7207083>.
License: MIT + file LICENSE
Encoding: UTF-8
Depends: R (>= 4.1.0)
Imports: graphics, grDevices, stats, utils
Suggests: did (>= 2.1.0), knitr, rmarkdown, testthat (>= 3.0.0)
Config/testthat/edition: 3
VignetteBuilder: knitr, rmarkdown
URL: https://github.com/ronwag2005/phdid
BugReports: https://github.com/ronwag2005/phdid/issues
Config/roxygen2/version: 8.1.0
NeedsCompilation: no
Packaged: 2026-09-07 12:58:30 UTC; rohanwagle
Author: Rohan Wagle [aut, cre, cph],
  Parush Arora [aut, cph]
Maintainer: Rohan Wagle <rohan.wagle_ug2023@ashoka.edu.in>
Repository: CRAN
Date/Publication: 2026-09-15 12:00:02 UTC
