Estimating Treatment Effects in Panel Data Without Parallel Trends

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteur principal: Ishimaru, Shoya
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866909988716281856
author Ishimaru, Shoya
author_facet Ishimaru, Shoya
contents This paper proposes a novel approach for estimating treatment effects in panel data settings, addressing key limitations of the standard difference-in-differences (DID) approach. The standard approach relies on the parallel trends assumption, implicitly requiring that unobservable factors correlated with treatment assignment be unidimensional, time-invariant, and affect untreated potential outcomes in an additively separable manner. This paper introduces a more flexible framework that allows for multidimensional unobservables and non-additive separability, and provides sufficient conditions for identifying the average treatment effect on the treated. An empirical application to job displacement reveals substantially smaller long-run earnings losses compared to the standard DID approach, demonstrating the framework's ability to account for unobserved heterogeneity that manifests as differential outcome trajectories between treated and control groups.
format Preprint
id arxiv_https___arxiv_org_abs_2601_08281
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Estimating Treatment Effects in Panel Data Without Parallel Trends
Ishimaru, Shoya
Econometrics
This paper proposes a novel approach for estimating treatment effects in panel data settings, addressing key limitations of the standard difference-in-differences (DID) approach. The standard approach relies on the parallel trends assumption, implicitly requiring that unobservable factors correlated with treatment assignment be unidimensional, time-invariant, and affect untreated potential outcomes in an additively separable manner. This paper introduces a more flexible framework that allows for multidimensional unobservables and non-additive separability, and provides sufficient conditions for identifying the average treatment effect on the treated. An empirical application to job displacement reveals substantially smaller long-run earnings losses compared to the standard DID approach, demonstrating the framework's ability to account for unobserved heterogeneity that manifests as differential outcome trajectories between treated and control groups.
title Estimating Treatment Effects in Panel Data Without Parallel Trends
topic Econometrics
url https://arxiv.org/abs/2601.08281