{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T05:02:16Z","timestamp":1792040536666,"version":"4.4.0"},"reference-count":56,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2022,6,8]],"date-time":"2022-06-08T00:00:00Z","timestamp":1654646400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2023,9,20]]},"abstract":"<jats:title>Summary<\/jats:title>\n                  <jats:p>Linear regressions with period and group fixed effects are widely used to estimate policie\u2019s effects: 26 of the 100 most cited papers published by the American Economic Review from 2015 to 2019 estimate such regressions. It has recently been shown that those regressions may produce misleading estimates if the policy\u2019s effect is heterogeneous between groups or over time, as is often the case. This survey reviews a fast-growing literature that documents this issue and that proposes alternative estimators robust to heterogeneous effects. We use those alternative estimators to revisit Wolfers (2006a).<\/jats:p>","DOI":"10.1093\/ectj\/utac017","type":"journal-article","created":{"date-parts":[[2022,6,8]],"date-time":"2022-06-08T13:21:59Z","timestamp":1654694519000},"page":"C1-C30","source":"Crossref","is-referenced-by-count":509,"title":["Two-way fixed effects and differences-in-differences with heterogeneous treatment effects: a survey"],"prefix":"10.1093","volume":"26","author":[{"given":"Cl\u00e9ment","family":"de\u00a0Chaisemartin","sequence":"first","affiliation":[{"name":"Economics Department , Sciences Po 28 rue des Saint-P\u00e8res, 75005 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xavier","family":"D\u2019Haultf\u0153uille","sequence":"additional","affiliation":[{"name":"Economics, CREST-ENSAE, 5 avenue Henry le Chatelier, 91120 Palaiseau , France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2022,6,8]]},"reference":[{"issue":"1","key":"2023092014142238300_bib1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/0034-6527.00321","article-title":"Semiparametric difference-in-differences estimators","volume":"72","author":"Abadie","year":"2005","journal-title":"Review of Economic Studies"},{"key":"2023092014142238300_bib2","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.jeconom.2020.10.012","article-title":"Design-based analysis in difference-in-differences settings with staggered adoption","volume":"226","author":"Athey","year":"2022","journal-title":"Journal of Econometrics"},{"issue":"2","key":"2023092014142238300_bib3","doi-asserted-by":"crossref","first-page":"370","DOI":"10.1016\/j.jfineco.2022.01.004","article-title":"How much should we trust staggered difference-in-differences estimates?","volume":"144","author":"Baker","year":"2022","journal-title":"Journal of Financial Economics"},{"key":"2023092014142238300_bib4","article-title":"Nothing to see here? 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