Release v3.5.2: version bump + CHANGELOG reconciliation

CITATION.cff

@@ -7,8 +7,8 @@ authors:
     family-names: Gerber
     orcid: "https://orcid.org/0009-0009-3275-5591"
 license: MIT
-version: "3.5.1"
-date-released: "2026-06-02"
+version: "3.5.2"
+date-released: "2026-06-08"
 doi: "10.5281/zenodo.19646175"
 url: "https://github.com/igerber/diff-diff"
 repository-code: "https://github.com/igerber/diff-diff"

diff_diff/__init__.py

@@ -298,7 +298,7 @@
 DCDH = ChaisemartinDHaultfoeuille
 HAD = HeterogeneousAdoptionDiD
 
-__version__ = "3.5.1"
+__version__ = "3.5.2"
 __all__ = [
     # Estimators
     "DifferenceInDifferences",

diff_diff/guides/llms-full.txt

@@ -2,7 +2,7 @@
 
 > A Python library for Difference-in-Differences causal inference analysis. Provides sklearn-like estimators with statsmodels-style output for econometric analysis.
 
-- Version: 3.5.1
+- Version: 3.5.2
 - Repository: https://github.com/igerber/diff-diff
 - License: MIT
 - Dependencies: numpy, pandas, scipy (no statsmodels dependency)

diff_diff/results.py

@@ -1209,13 +1209,11 @@ def coef_var(self) -> float:
     def placebo_effects(self) -> Optional[np.ndarray]:
         """Deprecated alias for :attr:`variance_effects` (removed in v4.0.0).
 
-        .. deprecated:: 3.6.0
+        .. deprecated:: 3.5.2
             Renamed to ``variance_effects`` because the array's contents are
             method-specific (placebo effects, bootstrap ATT draws, or
             leave-one-out estimates depending on ``variance_method``).
         """
-        # `3.6.0` is the assumed next-minor (current is 3.5.1); confirm/resolve
-        # at bump-version time. The v4.0.0 removal target is fixed.
         warnings.warn(
             "SyntheticDiDResults.placebo_effects is deprecated; use "
             "variance_effects instead. The array holds placebo effects, "

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "maturin"
 
 [project]
 name = "diff-diff"
-version = "3.5.1"
+version = "3.5.2"
 description = "Difference-in-Differences causal inference with sklearn-like API. Callaway-Sant'Anna, Synthetic DiD, Honest DiD, event studies, parallel trends."
 readme = "README.md"
 license = "MIT"

rust/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "diff_diff_rust"
-version = "3.5.1"
+version = "3.5.2"
 edition = "2021"
 rust-version = "1.85"
 description = "Rust backend for diff-diff DiD library"