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Simulations show that the plug-in tests are less conservative than identification-robust tests that use the original parametrization. An empirical application to a factor model of parental investments in children is included.<\/jats:p>","DOI":"10.1162\/rest_a_01441","type":"journal-article","created":{"date-parts":[[2024,3,18]],"date-time":"2024-03-18T12:58:29Z","timestamp":1710766709000},"page":"1109-1123","update-policy":"https:\/\/doi.org\/10.1162\/mitpressjournals.corrections.policy","source":"Crossref","is-referenced-by-count":1,"title":["Weak Identification in Low-Dimensional Factor Models with One or Two Factors"],"prefix":"10.1162","volume":"108","author":[{"given":"Gregory Fletcher","family":"Cox","sequence":"first","affiliation":[{"name":"National University of Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"281","published-online":{"date-parts":[[2026,7,17]]},"reference":[{"key":"2026072020514059100_bib1","doi-asserted-by":"publisher","first-page":"846","DOI":"10.1086\/733396","article-title":"Estimating the Technology of Children\u2019s Skill 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