IDEAS home Printed from https://ideas.repec.org/p/csa/wpaper/2016-38.html
   My bibliography  Save this paper

The Twin Instrument

Author

Listed:
  • Sonia Bhalotra
  • Damian Clarke

Abstract

Twin births are often construed as a natural experiment in the social and natural sciences on the premise that the occurrence of twins is quasi-random. We present new population-level evidence that challenges this premise. Using individual data for more than 18 million births (more than 500,000 of which are twins) in 72 countries, we demonstrate that indicators of the mother's health and health-related behaviours and exposures are systematically positively associated with the probability of a twin birth. The estimated associations are sizeable, evident in richer and poorer countries, and evident even in a sample of women who do not use IVF. The positive selection of women into twinning implies that estimates of impacts of fertility on parental investments and on women's labour supply that use twin births to instrument fertility will tend to be downward biased. This is pertinent given the emerging consensus that these relationships are weak. Using two large samples, one for developing countries and one for the United States, and focusing upon twin-instrumented estimates of the quantity-quality trade-off, we demonstrate the nature of the bias and estimate bounds on the true parameter.

Suggested Citation

  • Sonia Bhalotra & Damian Clarke, 2016. "The Twin Instrument," CSAE Working Paper Series 2016-38, Centre for the Study of African Economies, University of Oxford.
  • Handle: RePEc:csa:wpaper:2016-38
    as

    Download full text from publisher

    File URL: https://ora.ox.ac.uk/objects/uuid:cec160a2-2be1-4095-90ec-6dd7d4d8357a
    Download Restriction: no
    ---><---

    Other versions of this item:

    References listed on IDEAS

    as
    1. Emla Fitzsimons & Bansi Malde, 2014. "Empirically probing the quantity–quality model," Journal of Population Economics, Springer;European Society for Population Economics, vol. 27(1), pages 33-68, January.
    2. Sandra E. Black & Paul J. Devereux & Kjell G. Salvanes, 2005. "The More the Merrier? The Effect of Family Size and Birth Order on Children's Education," The Quarterly Journal of Economics, Oxford University Press, vol. 120(2), pages 669-700.
    3. Mark R. Rosenzweig & Junsen Zhang, 2009. "Do Population Control Policies Induce More Human Capital Investment? Twins, Birth Weight and China's "One-Child" Policy," Review of Economic Studies, Oxford University Press, vol. 76(3), pages 1149-1174.
    4. Hongbin Li & Junsen Zhang & Yi Zhu, 2008. "The quantity-Quality trade-Off of children In a developing country: Identification using chinese twins," Demography, Springer;Population Association of America (PAA), vol. 45(1), pages 223-243, February.
    5. Vladimir Ponczek & Andre Portela Souza, 2012. "New Evidence of the Causal Effect of Family Size on Child Quality in a Developing Country," Journal of Human Resources, University of Wisconsin Press, vol. 47(1), pages 64-106.
    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. Timothy G. Conley & Christian B. Hansen & Peter E. Rossi, 2012. "Plausibly Exogenous," The Review of Economics and Statistics, MIT Press, vol. 94(1), pages 260-272, February.
    8. Damian Clarke, 2014. "PLAUSEXOG: Stata module to implement Conley et al's plausibly exogenous bounds," Statistical Software Components S457832, Boston College Department of Economics, revised 08 Jul 2020.
    9. Julio Cáceres-Delpiano, 2006. "The Impacts of Family Size on Investment in Child Quality," Journal of Human Resources, University of Wisconsin Press, vol. 41(4).
    10. David S. Lee, 2009. "Training, Wages, and Sample Selection: Estimating Sharp Bounds on Treatment Effects," Review of Economic Studies, Oxford University Press, vol. 76(3), pages 1071-1102.
    Full references (including those not matched with items on IDEAS)

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Tabea Bucher-Koenen & Helmut Farbmacher & Raphael Guber & Johan Vikström, 2020. "Double Trouble: The Burden of Child-rearing and Working on Maternal Mortality," Demography, Springer;Population Association of America (PAA), vol. 57(2), pages 559-576, April.
    2. Richard Akresh & Sonia Bhalotra & Marinella Leone & Una Osili, 2017. "Hunger Games: First and Second Generation Impacts of the Biafran War," HiCN Working Papers 254, Households in Conflict Network.
    3. PONGOU Roland & SHAPIRO David & TENIKUE Michel, 2018. "Missing Twins: Fetal Origins, Institutions, and Twin-singleton Mortality Convergence," LISER Working Paper Series 2018-04, Luxembourg Institute of Socio-Economic Research (LISER).
    4. Sahawal Alidou & Marijke Verpoorten, 2019. "Family size and schooling in sub-Saharan Africa: testing the quantity-quality trade-off," Journal of Population Economics, Springer;European Society for Population Economics, vol. 32(4), pages 1353-1399, October.
    5. Erika Raquel Badillo & Lina Cardona-Sosa & Carlos Medina & Leonardo Fabio Morales & Christian Posso, 2019. "Twin instrument, fertility and women’s labor force participation: evidence from Colombian low-income families," Borradores de Economia 1071, Banco de la Republica de Colombia.
    6. Richard Akresh & Sonia Bhalotra & Marinella Leone & Una Osili, 2023. "First- and Second-Generation Impacts of the Biafran War," Journal of Human Resources, University of Wisconsin Press, vol. 58(2), pages 488-531.
    7. Aaronson, Daniel & Dehejia, Rajeev & Jordon, Andrew & Pop-Eleches, Cristian & Samii, Cyrus & Schultze, Karl, 2017. "The Effect of Fertility on Mothers’ Labor Supply over the Last Two Centuries," MPRA Paper 76768, University Library of Munich, Germany.
    8. Azam Mehtabul & Hang Saing Chan, 2018. "Is There Really a Trade-Off? Family Size and Investment in Child Quality in India," The B.E. Journal of Economic Analysis & Policy, De Gruyter, vol. 18(1), pages 1-12, January.
    9. Seongsoo Choi & Riley Taiji & Manting Chen & Christiaan Monden, 2020. "Cohort Trends in the Association Between Sibship Size and Educational Attainment in 26 Low-Fertility Countries," Demography, Springer;Population Association of America (PAA), vol. 57(3), pages 1035-1062, June.
    10. Jeanne Lafortune & Corinne Low, 2023. "Collateralized Marriage," American Economic Journal: Applied Economics, American Economic Association, vol. 15(4), pages 252-291, October.
    11. Ea Hoppe Blaabæk & Mads Meier Jæger & Joseph Molitoris, 2020. "Family Size and Educational Attainment: Cousins, Contexts, and Compensation," European Journal of Population, Springer;European Association for Population Studies, vol. 36(3), pages 575-600, July.
    12. Damian Clarke & Benjamín Matta, 2018. "Practical considerations for questionable IVs," Stata Journal, StataCorp LP, vol. 18(3), pages 663-691, September.
    13. Marie Baguet & Christelle Dumas, 2019. "How does birth weight affect health and human capital? A short‐ and long‐term evaluation," Health Economics, John Wiley & Sons, Ltd., vol. 28(5), pages 597-617, May.
    14. Anne (A.C.) Gielen & Esmee Zwiers, 2018. "Biology and the gender gap in educational performance - The role of prenatal testosterone in test scores," Tinbergen Institute Discussion Papers 18-086/V, Tinbergen Institute.
    15. Climent Quintana-Domeque & Pedro Rodenas-Serrano, 2014. "Terrorism and Human Capital at Birth: Bomb Casualties and Birth Outcomes in Spain," Working Papers 2014-020, Human Capital and Economic Opportunity Working Group.
    16. Wei Fan & Catherine Porter, 2020. "Reinforcement or compensation? Parental responses to children’s revealed human capital levels," Journal of Population Economics, Springer;European Society for Population Economics, vol. 33(1), pages 233-270, January.
    17. Hernando Vargas-Herrera & Mauricio Villamizar-Villegas, 2019. "Effectiveness of FX Intervention and the Flimsiness of Exchange rate Expectations," Borradores de Economia 1070, Banco de la Republica de Colombia.
    18. Fernihough, Alan, 2017. "Less is More? The child quantity-quality trade-off in early 20th century England and Wales," QUCEH Working Paper Series 2017-07, Queen's University Belfast, Queen's University Centre for Economic History.
    19. Damian Clarke, 2018. "Children And Their Parents: A Review Of Fertility And Causality," Journal of Economic Surveys, Wiley Blackwell, vol. 32(2), pages 518-540, April.
    20. Gitanjali Sen & Mitul Surana & Rakesh Basant, 2023. "To What Extent Does the Fertility Rate Explain the Education Gap?," Population Research and Policy Review, Springer;Southern Demographic Association (SDA), vol. 42(3), pages 1-31, June.
    21. Liang, Yun & Gibson, John, 2018. "Do siblings take your food away? Using China's one-child policy to test for child quantity-quality trade-offs," China Economic Review, Elsevier, vol. 48(C), pages 14-26.
    22. Baguet, Marie & Dumas, Christelle, 2015. "Birth weight and long-term outcomes in a developing country," FSES Working Papers 465, Faculty of Economics and Social Sciences, University of Freiburg/Fribourg Switzerland.

    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. Sonia Bhalotra & Damian Clarke, 2020. "The Twin Instrument: Fertility and Human Capital Investment," Journal of the European Economic Association, European Economic Association, vol. 18(6), pages 3090-3139.
    2. 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.
    3. Azam Mehtabul & Hang Saing Chan, 2018. "Is There Really a Trade-Off? Family Size and Investment in Child Quality in India," The B.E. Journal of Economic Analysis & Policy, De Gruyter, vol. 18(1), pages 1-12, January.
    4. Damian Clarke, 2018. "Children And Their Parents: A Review Of Fertility And Causality," Journal of Economic Surveys, Wiley Blackwell, vol. 32(2), pages 518-540, April.
    5. Sonia Bhalotra & Damian Clarke, 2019. "Twin Birth and Maternal Condition," The Review of Economics and Statistics, MIT Press, vol. 101(5), pages 853-864, December.
    6. Christina J. Diaz & Jeremy E. Fiel, 2021. "When Size Matters: IV Estimates of Sibship Size on Educational Attainment in the U.S," Population Research and Policy Review, Springer;Southern Demographic Association (SDA), vol. 40(6), pages 1195-1220, December.
    7. Ea Hoppe Blaabæk & Mads Meier Jæger & Joseph Molitoris, 2020. "Family Size and Educational Attainment: Cousins, Contexts, and Compensation," European Journal of Population, Springer;European Association for Population Studies, vol. 36(3), pages 575-600, July.
    8. Haoming Liu & Li Li, 2022. "The quantity–quality fertility–education trade-off," IZA World of Labor, Institute of Labor Economics (IZA), pages 143-143, March.
    9. Timothy J. Hatton, 2015. "Stature and Sibship: Historical Evidence," CEH Discussion Papers 039, Centre for Economic History, Research School of Economics, Australian National University.
    10. Oliveira, Jaqueline, 2016. "The value of children: Inter-generational support, fertility, and human capital," Journal of Development Economics, Elsevier, vol. 120(C), pages 1-16.
    11. Philip DeCicca & Harry Krashinsky, 2023. "The effect of education on overall fertility," Journal of Population Economics, Springer;European Society for Population Economics, vol. 36(1), pages 471-503, January.
    12. Li, Bingjing & Zhang, Hongliang, 2017. "Does population control lead to better child quality? Evidence from China’s one-child policy enforcement," Journal of Comparative Economics, Elsevier, vol. 45(2), pages 246-260.
    13. Jianmei ZHAO & Hai ZHONG, 2019. "A Demographic Factor as a Determinant of Migration: What Is the Effect of Sibship Size on Migration Decision?," JODE - Journal of Demographic Economics, Cambridge University Press, vol. 85(4), pages 321-345, December.
    14. Christelle DUMAS & Arnaud LEFRANC, 2013. ""Sex in Marriage is a Divine Gift": For whom ? Evidence from the Manila contraceptive ban," THEMA Working Papers 2013-22, THEMA (THéorie Economique, Modélisation et Applications), Université de Cergy-Pontoise.
    15. Hai-Anh H. Dang & F. Halsey Rogers, 2016. "The Decision to Invest in Child Quality over Quantity: Household Size and Household Investment in Education in Vietnam," The World Bank Economic Review, World Bank Group, vol. 30(1), pages 104-142.
    16. Yusuf Sofiyandi1, 2018. "The Effect of Residential Location and Housing Unit Characteristics on Labor Force Participation of Childbearing Women in Indonesia: Using Twin Births As A Quasi-Natural Experiment," LPEM FEBUI Working Papers 201822, LPEM, Faculty of Economics and Business, University of Indonesia, revised Jul 2018.
    17. Dasgupta, Kabir & Solomon, Keisha T., 2018. "Family size effects on childhood obesity: Evidence on the quantity-quality trade-off using the NLSY," Economics & Human Biology, Elsevier, vol. 29(C), pages 42-55.
    18. 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.
    19. Marc Klemp & Jacob Weisdorf, 2019. "Fecundity, Fertility and The Formation of Human Capital," The Economic Journal, Royal Economic Society, vol. 129(618), pages 925-960.
    20. Gitanjali Sen & Mitul Surana & Rakesh Basant, 2023. "To What Extent Does the Fertility Rate Explain the Education Gap?," Population Research and Policy Review, Springer;Southern Demographic Association (SDA), vol. 42(3), pages 1-31, June.

    More about this item

    Keywords

    Twins; fertility; maternal health; miscarriage; quantity-quality trade-off; parental investment; bounds;
    All these keywords.

    JEL classification:

    • J12 - Labor and Demographic Economics - - Demographic Economics - - - Marriage; Marital Dissolution; Family Structure
    • J13 - Labor and Demographic Economics - - Demographic Economics - - - Fertility; Family Planning; Child Care; Children; Youth
    • C13 - Mathematical and Quantitative Methods - - Econometric and Statistical Methods and Methodology: General - - - Estimation: General
    • D13 - Microeconomics - - Household Behavior - - - Household Production and Intrahouse Allocation
    • I12 - Health, Education, and Welfare - - Health - - - Health Behavior

    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:csa:wpaper:2016-38. 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: Julia Coffey (email available below). General contact details of provider: https://edirc.repec.org/data/csaoxuk.html .

    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.