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Unlike our estimators, they can be biased in the presence of heterogeneous treatment effects. A local-projection version of those regressions is biased even with homogeneous effects.<\/jats:p>","DOI":"10.1162\/rest_a_01414","type":"journal-article","created":{"date-parts":[[2024,2,9]],"date-time":"2024-02-09T20:50:03Z","timestamp":1707511803000},"page":"863-880","update-policy":"https:\/\/doi.org\/10.1162\/mitpressjournals.corrections.policy","source":"Crossref","is-referenced-by-count":371,"title":["Difference-in-Differences Estimators of Intertemporal Treatment Effects"],"prefix":"10.1162","volume":"108","author":[{"given":"Cl\u00e9ment","family":"de Chaisemartin","sequence":"first","affiliation":[{"name":"Sciences Po Paris, Economics Department"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xavier","family":"D\u2019Haultf\u0153uille","sequence":"additional","affiliation":[{"name":"CREST-ENSAE and Institut Polytechnique de 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