{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T13:43:47Z","timestamp":1790775827627,"version":"4.1.0"},"reference-count":46,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T00:00:00Z","timestamp":1677196800000},"content-version":"vor","delay-in-days":444,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"DOI":"10.13039\/100000138","name":"U.S. Department of Education","doi-asserted-by":"publisher","award":["R305D200010"],"award-info":[{"award-number":["R305D200010"]}],"id":[{"id":"10.13039\/100000138","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2022,4,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Staggered adoption of policies by different units at different times creates promising opportunities for observational causal inference. Estimation remains challenging, however, and common regression methods can give misleading results. A promising alternative is the synthetic control method (SCM), which finds a weighted average of control units that closely balances the treated unit\u2019s pre-treatment outcomes. In this paper, we generalize SCM, originally designed to study a single treated unit, to the staggered adoption setting. We first bound the error for the average effect and show that it depends on both the imbalance for each treated unit separately and the imbalance for the average of the treated units. We then propose \u2018partially pooled\u2019 SCM weights to minimize a weighted combination of these measures; approaches that focus only on balancing one of the two components can lead to bias. We extend this approach to incorporate unit-level intercept shifts and auxiliary covariates. We assess the performance of the proposed method via extensive simulations and apply our results to the question of whether teacher collective bargaining leads to higher school spending, finding minimal impacts. We implement the proposed method in the augsynth R package.<\/jats:p>","DOI":"10.1111\/rssb.12448","type":"journal-article","created":{"date-parts":[[2021,12,7]],"date-time":"2021-12-07T21:46:35Z","timestamp":1638913595000},"page":"351-381","source":"Crossref","is-referenced-by-count":116,"title":["Synthetic Controls with Staggered Adoption"],"prefix":"10.1093","volume":"84","author":[{"given":"Eli","family":"Ben-Michael","sequence":"first","affiliation":[{"name":"Harvard University , Cambridge, Massachusetts , USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Avi","family":"Feller","sequence":"additional","affiliation":[{"name":"University of California , Berkeley, California , USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jesse","family":"Rothstein","sequence":"additional","affiliation":[{"name":"University of California , Berkeley, California , USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2021,12,7]]},"reference":[{"issue":"1","key":"2023022501101808000_","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":"The Review of Economic Studies"},{"key":"2023022501101808000_","doi-asserted-by":"crossref","first-page":"391","DOI":"10.1257\/jel.20191450","article-title":"Using synthetic controls: feasibility, data requirements, and methodological aspects","volume":"59","author":"Abadie","year":"2019","journal-title":"Journal of Economic Literature"},{"key":"2023022501101808000_","first-page":"1","article-title":"A penalized synthetic control estimator for disaggregated data","author":"Abadie","year":"2021","journal-title":"Journal of the American Statistical Association"},{"issue":"490","key":"2023022501101808000_","doi-asserted-by":"crossref","first-page":"493","DOI":"10.1198\/jasa.2009.ap08746","article-title":"Synthetic control methods for comparative case studies: estimating the effect of California's tobacco control program","volume":"105","author":"Abadie","year":"2010","journal-title":"Journal of the American Statistical Association"},{"issue":"2","key":"2023022501101808000_","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1111\/ajps.12116","article-title":"Comparative politics and the synthetic control method","volume":"59","author":"Abadie","year":"2015","journal-title":"American Journal of Political Science"},{"issue":"5","key":"2023022501101808000_","doi-asserted-by":"crossref","first-page":"1491","DOI":"10.1111\/1468-0262.00456","article-title":"The nonparametric identification of treatment effects in duration models","volume":"71","author":"Abbring","year":"2003","journal-title":"Econometrica"},{"key":"2023022501101808000_","article-title":"Synthetic differences in differences","author":"Arkhangelsky","year":"2019","journal-title":"American Economic Review. 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