IDEAS home Printed from https://ideas.repec.org/p/osf/socarx/zux9s_v1.html
   My bibliography  Save this paper

Instrumental variables based on twin births are by definition not valid (v.3.0)

Author

Listed:
  • Öberg, Stefan

Abstract

Twin births are a well-known and widespread example of a so-called “natural experiment”. Instrumental variables based on twin births have been used in many studies to estimate the causal effect of the number of children on the parents or siblings. I use the potential outcomes framework to show that these instrumental variables do not work as intended. They are fundamentally flawed and will always lead to severely biased estimates without any meaningful interpretation. This has been overlooked in previous research because too little attention has been paid to defining the treatment in this natural experiment. I analyze three different possible interpretations of the treatment and show that they all lead to inherent violations of the necessary assumptions. The effect of the number of on the parents or siblings is a policy relevant and theoretically important issue. The scientific record should therefore be corrected to not lead to misguided decisions.

Suggested Citation

  • Öberg, Stefan, 2018. "Instrumental variables based on twin births are by definition not valid (v.3.0)," SocArXiv zux9s_v1, Center for Open Science.
    • Handle: RePEc:osf:socarx:zux9s_v1
    DOI: 10.31219/osf.io/zux9s_v1
    as

    Download full text from publisher

    File URL: https://osf.io/download/594e98af6c613b0229e383e2/
    Download Restriction: no
    File URL: https://libkey.io/10.31219/osf.io/zux9s_v1?utm_source=ideas
    LibKey link: if access is restricted and if your library uses this service, LibKey will redirect you to where you can use your library subscription to access this item
    ---><---

    References listed on IDEAS

    as
    1. Guo, Rufei & Li, Hongbin & Yi, Junjian & Zhang, Junsen, 2018. "Fertility, household structure, and parental labor supply: Evidence from China," Journal of Comparative Economics, Elsevier, vol. 46(1), pages 145-156.
    2. Julie Moschion, 2013. "The Impact of Fertility on Mothers' Labour Supply in Australia: Evidence from Exogenous Variation in Family Size," The Economic Record, The Economic Society of Australia, vol. 89(286), pages 319-338, September.
    3. Guo, Rufei & Yi, Junjian & Zhang, Junsen, 2017. "Family size, birth order, and tests of the quantity–quality model," Journal of Comparative Economics, Elsevier, vol. 45(2), pages 219-224.
    4. repec:adr:anecst:y:2010:i:99-100:p:10 is not listed on IDEAS
    5. Marc Frenette, 2011. "How does the stork delegate work? Childbearing and the gender division of paid and unpaid labour," Journal of Population Economics, Springer;European Society for Population Economics, vol. 24(3), pages 895-910, July.
    6. Joshua Angrist & Victor Lavy & Analia Schlosser, 2010. "Multiple Experiments for the Causal Link between the Quantity and Quality of Children," Journal of Labor Economics, University of Chicago Press, vol. 28(4), pages 773-824, October.
    7. Julie Moschion, 2010. "Reconciling Work and Family Life: The Effect of the French Paid Parental Leave," Annals of Economics and Statistics, GENES, issue 99-100, pages 217-246.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Öberg, Stefan, 2018. "Instrumental variables based on twin births are by definition not valid (v.3.0)," SocArXiv zux9s, Center for Open Science.
    2. KUEPIE Mathias & DZOSSA Anaclet Désiré & KELODJOUE Samuel, 2013. "Determinants of labor market gender inequalities in Cameroon, Senegal and Mali: the role of human capital and the fertility burden," LISER Working Paper Series 2013-08, Luxembourg Institute of Socio-Economic Research (LISER).
    3. Semih Tumen & Belgi Turan, 2023. "The effect of fertility on female labor supply in a labor market with extensive informality," Empirical Economics, Springer, vol. 65(4), pages 1855-1894, October.
    4. Idriss Fontaine, 2018. "L’effet causal du nombre d’enfants sur l’offre de travail des mères : le cas de la France métropolitaine et de ses départements d’outre-mer," Revue économique, Presses de Sciences-Po, vol. 69(5), pages 869-898.
    5. Julie Moschion, 2013. "The Impact of Fertility on Mothers' Labour Supply in Australia: Evidence from Exogenous Variation in Family Size," The Economic Record, The Economic Society of Australia, vol. 89(286), pages 319-338, September.
    6. Chae, Minhee & Meng, Xin & Xue, Sen, 2023. "Fertility, Son-Preference, and the Reversal of the Gender Gap in Literacy/Numeracy Tests," IZA Discussion Papers 16208, Institute of Labor Economics (IZA).
    7. Kaat Van Hoyweghen & Janne Bemelmans & Hendrik Feyaerts & Goedele Van den Broeck & Miet Maertens, 2023. "Small Family, Happy Family? Fertility Preferences and the Quantity–Quality Trade-Off in Sub-Saharan Africa," Population Research and Policy Review, Springer;Southern Demographic Association (SDA), vol. 42(6), pages 1-35, December.
    8. Beatrice Baaba Tawiah, 2023. "The Effect of Children on Health," Working Papers Dissertations 103, Paderborn University, Faculty of Business Administration and Economics.
    9. Meng, Lina & Peng, Lu & Zhou, Yinggang, 2023. "Do housing booms reduce fertility intentions? Evidence from the new two-child policy in China," Regional Science and Urban Economics, Elsevier, vol. 101(C).
    10. Kouki, Amairisa, 2023. "Beyond the “Comforts” of work from home: Child health and the female wage penalty," European Economic Review, Elsevier, vol. 157(C).
    11. Luc Behaghel & Maria Florencia Pinto, 2024. "Extended maternity leave and children's long‐term development," Scandinavian Journal of Economics, Wiley Blackwell, vol. 126(2), pages 224-253, April.
    12. Peng, Fei & Anwar, Sajid & Kang, Lili, 2022. "Number of siblings, access to treated water and returns to education in China," Economic Analysis and Policy, Elsevier, vol. 74(C), pages 526-538.
    13. Shuang Chen, 2020. "Parental Investment After the Birth of a Sibling: The Effect of Family Size in Low-Fertility China," Demography, Springer;Population Association of America (PAA), vol. 57(6), pages 2085-2111, December.
    14. Adriana D. Kugler & Santosh Kumar, 2017. "Preference for Boys, Family Size, and Educational Attainment in India," Demography, Springer;Population Association of America (PAA), vol. 54(3), pages 835-859, June.
    15. Lahiri, Bidisha & Ali, Haider, 2022. "Inspections, informal payments and tax payments by firms," Finance Research Letters, Elsevier, vol. 46(PA).
    16. Nooshin Rashti Mohammad & Ali Taieb Nia & Sajjad Barkhordari, 2024. "The Casual Effect of Family Size on the Human Capital in Iranian Society," Journal of the Knowledge Economy, Springer;Portland International Center for Management of Engineering and Technology (PICMET), vol. 15(1), pages 4056-4071, March.
    17. Chen, Cheng & Zhao, Wangyang & Chou, Shin-Yi & Lien, Hsien-Ming, 2021. "The effect of family size on parents' labor supply and occupational prestige: Evidence from Taiwan and Mainland China," China Economic Review, Elsevier, vol. 66(C).
    18. Briole, Simon & Le Forner, Hélène & Lepinteur, Anthony, 2020. "Children’s socio-emotional skills: Is there a quantity–quality trade-off?," Labour Economics, Elsevier, vol. 64(C).
    19. Vincent Bignon & Cecilia Garcia-Peñalosa, 2018. "The Toll of Tariffs: Protectionism, Education and Fertility in Late 19th Century France," Working papers 690, Banque de France.
    20. Manuel Denzer, 2019. "Estimating Causal Effects in Binary Response Models with Binary Endogenous Explanatory Variables - A Comparison of Possible Estimators," Working Papers 1916, Gutenberg School of Management and Economics, Johannes Gutenberg-Universität Mainz.

    More about this item

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:osf:socarx:zux9s_v1. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: OSF (email available below). General contact details of provider: https://arabixiv.org .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.