IDEAS home Printed from
   My bibliography  Save this paper

Running and Jumping Variables in RD Designs


  • Alan Barreca


  • Melanie Guldi


  • Jason M. Lindo


  • Glen R. Waddell

    () (Department of Economics, Tulane University)


This study demonstrates that regression discontinuity designs will arrive at biased estimates when attributes related to outcomes predict heaping in the running variable. We discuss several approaches to diagnosing and correcting for this type of problem. Our primary example focuses on the use of birth weights as a running variable. We begin by showing that birth weights are measured most precisely for children of white and highly educated mothers. As a result, less healthy children, who are more likely to be of low socioeconomic status, are disproportionately represented at multiples of round numbers. For this reason, RD estimates using birth weight as the running variable will be biased in a manner that leads one to conclude that it is "good" to be strictly less than any 100-gram cutoff. As such, prior estimates of the effects of very low birth weight classification (Almond, Doyle, Kowalski, and Williams 2010) have been overstated and appear to be zero. We also demonstrate potential problems using days of birth or grade point averages as running variables.

Suggested Citation

  • Alan Barreca & Melanie Guldi & Jason M. Lindo & Glen R. Waddell, 2010. "Running and Jumping Variables in RD Designs," Working Papers 1001, Tulane University, Department of Economics.
  • Handle: RePEc:tul:wpaper:1001

    Download full text from publisher

    File URL:
    File Function: First version, 2010
    Download Restriction: no

    File URL:
    File Function: Revised version, 2011
    Download Restriction: no

    References listed on IDEAS

    1. Peter Warr, 2008. "World food prices and poverty incidence in a food exporting country: a multihousehold general equilibrium analysis for Thailand," Agricultural Economics, International Association of Agricultural Economists, vol. 39(s1), pages 525-537, November.
    2. Joachim von Braun, 2008. "Rising Food Prices: What Should Be Done?," EuroChoices, The Agricultural Economics Society, vol. 7(SpecialIs), pages 30-35, August.
    3. Maros Ivanic & Will Martin, 2008. "Implications of higher global food prices for poverty in low-income countries-super-1," Agricultural Economics, International Association of Agricultural Economists, vol. 39(s1), pages 405-416, November.
    4. Mellor, John W, 1978. "Food Price Policy and Income Distribution in Low-Income Countries," Economic Development and Cultural Change, University of Chicago Press, vol. 27(1), pages 1-26, October.
    5. Trostle, Ronald, 2008. "Factors Contributing to Recent Increases in Food Commodity Prices (PowerPoint)," Seminars 43902, USDA Economists Group.
    6. Christopher B. Barrett & Paul A. Dorosh, 1996. "Farmers' Welfare and Changing Food Prices: Nonparametric Evidence from Rice in Madagascar," American Journal of Agricultural Economics, Agricultural and Applied Economics Association, vol. 78(3), pages 656-669.
    7. Abbott, Philip C. & Hurt, Christopher & Tyner, Wallace E., 2008. "What's Driving Food Prices?," Issue Reports 37951, Farm Foundation.
    8. Jorge N. Valero-Gil & Magali Valero, 2008. "The effects of rising food prices on poverty in Mexico," Agricultural Economics, International Association of Agricultural Economists, vol. 39(s1), pages 485-496, November.
    9. Zahoor ul Haq & Hina Nazli & Karl Meilke, 2008. "Implications of high food prices for poverty in Pakistan," Agricultural Economics, International Association of Agricultural Economists, vol. 39(s1), pages 477-484, November.
    10. S├ębastien Dessus & Santiago Herrera & Rafael de Hoyos, 2008. "The impact of food inflation on urban poverty and its monetary cost: some back-of-the-envelope calculations," Agricultural Economics, International Association of Agricultural Economists, vol. 39(s1), pages 417-429, November.
    11. Ravallion, Martin, 1990. "Rural Welfare Effects of Food Price Changes under Induced Wage Responses: Theory and Evidence for Bangladesh," Oxford Economic Papers, Oxford University Press, vol. 42(3), pages 574-585, July.
    12. Quentin Wodon & Hassan Zaman, 2010. "Higher Food Prices in Sub-Saharan Africa: Poverty Impact and Policy Responses," World Bank Research Observer, World Bank Group, vol. 25(1), pages 157-176, February.
    13. Trairatvorakul, Prasarn, 1984. "The effects on income distribution and nutrition of alternative rice price policies in Thailand:," Research reports 46, International Food Policy Research Institute (IFPRI).
    14. Deaton, Angus, 1989. "Rice Prices and Income Distribution in Thailand: A Non-parametric Analysis," Economic Journal, Royal Economic Society, vol. 99(395), pages 1-37, Supplemen.
    15. John Baffes, 1997. "Explaining stationary variables with non-stationary regressors," Applied Economics Letters, Taylor & Francis Journals, vol. 4(1), pages 69-75.
    16. Kimberly Elliott, 2008. "Biofuels and the Food Price Crisis: A Survey of the Issues," Working Papers 151, Center for Global Development.
    17. Jeffrey A. Frankel, 2008. "The Effect of Monetary Policy on Real Commodity Prices," NBER Chapters,in: Asset Prices and Monetary Policy, pages 291-333 National Bureau of Economic Research, Inc.
    18. Dermot Gately & Hiliard G. Huntington, 2002. "The Asymmetric Effects of Changes in Price and Income on Energy and Oil Demand," The Energy Journal, International Association for Energy Economics, vol. 0(Number 1), pages 19-55.
    19. Charles Ackah, & Simon Appleton, "undated". "Food Price Changes and Consumer Welfare in Ghana in the 1990s," Discussion Papers 07/03, University of Nottingham, CREDIT.
    20. Ivanic, Maros & Martin, Will, 2008. "Implications of higher global food prices for poverty in low-income countries," Policy Research Working Paper Series 4594, The World Bank.
    21. Mitchell, Donald, 2008. "A note on rising food prices," Policy Research Working Paper Series 4682, The World Bank.
    22. Ravallion, Martin & van de Walle, Dominique, 1991. "The impact on poverty of food pricing reforms: A welfare analysis for Indonesia," Journal of Policy Modeling, Elsevier, vol. 13(2), pages 281-299.
    23. Lihong Lu McPhail & Bruce A. Babcock, 2008. "Short-Run Price and Welfare Impacts of Federal Ethanol Policies," Center for Agricultural and Rural Development (CARD) Publications 08-wp468, Center for Agricultural and Rural Development (CARD) at Iowa State University.
    24. von Braun, Joachim & Ahmed, Akhter & Asenso-Okyere, Kwadwo & Fan, Shenggen & Gulati, Ashok & Hoddinott, John & Pandya-Lorch, Rajul & Rosegrant, Mark W. & Ruel, Marie & Torero, Maximo & van Rheenen, Te, 2008. "High food prices: The what, who, and how of proposed policy actions," Policy briefs 1A, International Food Policy Research Institute (IFPRI).
    25. Wodon, Quentin & Zaman, Hassan, 2008. "Rising food prices in Sub-Saharan Africa : poverty impact and policy responses," Policy Research Working Paper Series 4738, The World Bank.
    Full references (including those not matched with items on IDEAS)


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

    Cited by:

    1. Sa A. Bui & Steven G. Craig & Scott A. Imberman, 2011. "Is Gifted Education a Bright Idea? Assessing the Impact of Gifted and Talented Programs on Achievement," NBER Working Papers 17089, National Bureau of Economic Research, Inc.
    2. Paco Martorell & Isaac McFarlin, Jr. & Yu Xue, 2014. "Does Failing a Placement Exam Discourage Underprepared Students from Going to College?," Education Finance and Policy, MIT Press, vol. 10(1), pages 46-80, November.

    More about this item


    regression discontinuity; birth weight; infant mortality;

    JEL classification:

    • C21 - Mathematical and Quantitative Methods - - Single Equation Models; Single Variables - - - Cross-Sectional Models; Spatial Models; Treatment Effect Models
    • C14 - Mathematical and Quantitative Methods - - Econometric and Statistical Methods and Methodology: General - - - Semiparametric and Nonparametric Methods: General
    • I12 - Health, Education, and Welfare - - Health - - - Health Behavior

    NEP fields

    This paper has been announced in the following NEP Reports:


    Access and download statistics


    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:tul:wpaper:1001. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Rodrigo Aranda Balcazar). General contact details of provider: .

    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.

    We have no references for this item. You can help adding them by using 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.

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

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.