Экономисты опровергли популярное правило «F больше 10» при использовании слабых инструментов

Journal of Economic Perspectives ISSN 0895-3309 (Print) | ISSN 1944-7965 (Online) EditorsEditorial PolicyAnnual Report of the EditorResearch HighlightsReading RecommendationsJEP in the ClassroomContact InformationCurrent IssueAll IssuesGuidelines for Proposals Menu EditorsEditorial PolicyAnnual Report of the EditorResearch HighlightsReading RecommendationsJEP in the ClassroomContact InformationCurrent IssueAll IssuesGuidelines for Proposals Correct (and Incorrect) Inference with a Single Instrumental Variable: Practical Takeaways from the Weak Instruments Literature David S. Lee Jack Porter Journal of Economic Perspectives vol. 40, no. 3, Summer 2026 (pp. 193–212) Download Full Text PDF (Complimentary) Article Information Abstract Most empirical economists have encountered the warning that instrumental variables can be "weak," but the underlying issues—what makes an instrument weak, why weakness distorts inference, and what to do about it—are less widely understood. This article offers an accessible introduction to the weak instruments problem for the common just-identified case of a single endogenous regressor and a single instrument. We explain why the usual two-stage least squares t-ratio and its "±1.96 times the standard error" confidence interval can yield incorrect inferences, much as homoskedasticity-only standard errors do when errors are not homoskedastic. We then describe practical, robust-to-weak-instrument solutions—including the Anderson-Rubin and tF methods—that deliver valid confidence intervals whatever the instrument's true strength, and we offer some do's and don'ts, notably why the popular "F greater than 10" rule has no theoretical justification in this setting. Citation Lee, David S., and Jack Porter. 2026. "Correct (and Incorrect) Inference with a Single Instrumental Variable: Practical Takeaways from the Weak Instruments Literature." Journal of Economic Perspectives 40 (3): 193–212. DOI: 10.1257/jep.20251464 Additional Materials Replication Package Author Disclosure Statement(s) Exhibit Data JEL Classification C13 Estimation: General C26 Single Equation Models: Single Variables: Instrumental Variables (IV) Estimation I26 Returns to Education J24 Human Capital; Skills; Occupational Choice; Labor Productivity J31 Wage Level and Structure; Wage Differentials This website uses cookies. By clicking the "Accept" button or continuing to browse our site, you agree to first-party and session-only cookies being stored on your device to enhance site navigation and analyze site performance and traffic. For more information on our use of cookies, please see our Privacy Policy.