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Simple Tests for Selection: Learning More from Instrumental Variables

Author

Listed:
  • Dan A. Black
  • Joonhwi Joo
  • Robert LaLonde
  • Jeffrey Andrew Smith
  • Evan J. Taylor

Abstract

We provide simple tests for selection on unobserved variables in the Vytlacil-Imbens-Angrist framework for Local Average Treatment Effects. The tests allow researchers not only to test for selection on either or both of the treated and untreated outcomes, but also to assess the magnitude of the selection effect. The tests are quite simple; undergraduates after an introductory econometrics class should be able to implement these tests. We illustrate our tests with two empirical applications: the impact of children on female labor supply from Angrist and Evans (1998) and the impact of training on adult women from the Job Training Partnership Act (JTPA) experiment.

Suggested Citation

  • Dan A. Black & Joonhwi Joo & Robert LaLonde & Jeffrey Andrew Smith & Evan J. Taylor, 2017. "Simple Tests for Selection: Learning More from Instrumental Variables," CESifo Working Paper Series 6392, CESifo.
    • Handle: RePEc:ces:ceswps:_6392
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    Cited by:

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    3. Jeffrey Smith, 2022. "Treatment Effect Heterogeneity," Evaluation Review, , vol. 46(5), pages 652-677, October.
    4. Nocito, Samuel, 2021. "The effect of a university degree in english on international labor mobility," Labour Economics, Elsevier, vol. 68(C).
    5. Seth Gershenson & Cassandra M. D. Hart & Joshua Hyman & Constance A. Lindsay & Nicholas W. Papageorge, 2022. "The Long-Run Impacts of Same-Race Teachers," American Economic Journal: Economic Policy, American Economic Association, vol. 14(4), pages 300-342, November.
    6. Bjerk, David J., 2025. "Understanding IV Versus OLS Estimates of Treatment Effects and the Coefficient Difference Check," IZA Discussion Papers 18274, IZA Network @ LISER.
    7. Valentina Corradi & Daniel Gutknecht, 2019. "Testing for Quantile Sample Selection," Papers 1907.07412, arXiv.org, revised Jan 2021.
    8. Kim, Jun Hyung & Schulz, Wolfgang & Zimmermann, Tanja & Hahlweg, Kurt, 2018. "Parent–child interactions and child outcomes: Evidence from randomized intervention," Labour Economics, Elsevier, vol. 54(C), pages 152-171.
    9. Daniel Litwok, 2023. "Estimating the Impact of Emergency Assistance on Educational Progress for Low-Income Adults: Experimental and Nonexperimental Evidence," Evaluation Review, , vol. 47(2), pages 231-263, April.
    10. Fenoll, Ainoa Aparicio & Campaniello, Nadia & Monzón, Ignacio, 2025. "Parental love is not blind: Identifying selection into early school start," European Economic Review, Elsevier, vol. 180(C).

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    JEL classification:

    • C26 - Mathematical and Quantitative Methods - - Single Equation Models; Single Variables - - - Instrumental Variables (IV) Estimation
    • C52 - Mathematical and Quantitative Methods - - Econometric Modeling - - - Model Evaluation, Validation, and Selection
    • C93 - Mathematical and Quantitative Methods - - Design of Experiments - - - Field Experiments

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