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Is Child Work Necessary?

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  • Sonia R Bhalotra
Abstract
This paper investigates why children work by studying the wage elasticity of child labour supply. Incorporating subsistence constraints in to a model of labour supply, we show that a negative wage elasticity favours the hypothesis that poverty compels work whereas a positive wage elasticity would favour the alternative view that children work because the relative returns to school are low. Distinguishing between these alternatives is important for policy. Existing studies have concentrated on the income elasticity, but this tells us nothing other than that leisure (or education) is a normal good. Using a large household survey for rural Pakistan, we estimate structural labour supply models for boys and girls in wage work, conditioning on full income and a range of demographic variables. Our estimates describe a forward falling labour supply curve for boys, consistent with the view that boys work on account of the compulsions of poverty. This is less clear in the case of girls. Therefore raising the return to schooling for girls may draw them out of work, but eliminating boys' wage work requires alleviation of the poverty of their households. Trade sanctions or bans on child labour may have deleterious consequences for these households unless they are compensated for the loss in income.

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  • Sonia R Bhalotra, 2000. "Is Child Work Necessary?," STICERD - Development Economics Papers - From 2008 this series has been superseded by Economic Organisation and Public Policy Discussion Papers 26, Suntory and Toyota International Centres for Economics and Related Disciplines, LSE.
  • Handle: RePEc:cep:stidep:26
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    1. Richard Blundell & Ian Walker, 1986. "A Life-Cycle Consistent Empirical Model of Family Labour Supply Using Cross-Section Data," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 53(4), pages 539-558.
    2. Emmanuel Skoufias & Susan Wendy Parker, 2001. "Conditional Cash Transfers and Their Impact on Child Work and Schooling: Evidence from the PROGRESA Program in Mexico," Economía Journal, The Latin American and Caribbean Economic Association - LACEA, vol. 0(Fall 2001), pages 45-96, August.
    3. Altonji, Joseph G, 1986. "Intertemporal Substitution in Labor Supply: Evidence from Micro Data," Journal of Political Economy, University of Chicago Press, vol. 94(3), pages 176-215, June.
    4. Alok Bhargava & J. D. Sargan, 2006. "Estimating Dynamic Random Effects Models From Panel Data Covering Short Time Periods," World Scientific Book Chapters, in: Econometrics, Statistics And Computational Approaches In Food And Health Sciences, chapter 1, pages 3-27, World Scientific Publishing Co. Pte. Ltd..
    5. Edmonds, Eric V., 2008. "Child Labor," Handbook of Development Economics, in: T. Paul Schultz & John A. Strauss (ed.), Handbook of Development Economics, edition 1, volume 4, chapter 57, pages 3607-3709, Elsevier.
    6. Levy, Victor, 1985. "Cropping Pattern, Mechanization, Child Labor, and Fertility Behavior in a Farming Economy: Rural Egypt," Economic Development and Cultural Change, University of Chicago Press, vol. 33(4), pages 777-791, July.
    7. Kaushik Basu, 1999. "Child Labor: Cause, Consequence, and Cure, with Remarks on International Labor Standards," Journal of Economic Literature, American Economic Association, vol. 37(3), pages 1083-1119, September.
    8. Basu, Kaushik, 2000. "The Intriguing Relation between Adult Minimum Wage and Child Labour," Economic Journal, Royal Economic Society, vol. 110(462), pages 50-61, March.
    9. Canagarajah, Sudharshan & Coulombe, Harold, 1997. "Child labor and schooling in Ghana," Policy Research Working Paper Series 1844, The World Bank.
    10. Kooreman, Peter & Kapteyn, Arie, 1986. "Estimation of Rationed and Unrationed Household Labour Supply Functions Using Flexible Functional Forms," Economic Journal, Royal Economic Society, vol. 96(382), pages 398-412, June.
    11. Richard Blundell & John Ham & Costas Meghir, 1989. "Unemployment and Female Labour Supply," Palgrave Macmillan Books, in: Joan Muysken & Chris Neubourg (ed.), Unemployment in Europe, chapter 1, pages 9-36, Palgrave Macmillan.
    12. Appleton, S., 2000. "Education and Health at the Household Level in Sub-Saharan Africa," Papers 33, Chicago - Graduate School of Business.
    13. Newey, Whitney K & Powell, James L & Walker, James R, 1990. "Semiparametric Estimation of Selection Models: Some Empirical Results," American Economic Review, American Economic Association, vol. 80(2), pages 324-328, May.
    14. Blundell, Richard & Macurdy, Thomas, 1999. "Labor supply: A review of alternative approaches," Handbook of Labor Economics, in: O. Ashenfelter & D. Card (ed.), Handbook of Labor Economics, edition 1, volume 3, chapter 27, pages 1559-1695, Elsevier.
    15. Jafarey, Saqib & Lahiri, Sajal, 2002. "Will trade sanctions reduce child labour?: The role of credit markets," Journal of Development Economics, Elsevier, vol. 68(1), pages 137-156, June.
    16. David Card, 1994. "Earnings, Schooling, and Ability Revisited," Working Papers 710, Princeton University, Department of Economics, Industrial Relations Section..
    17. Hanan G. Jacoby & Emmanuel Skoufias, 1997. "Risk, Financial Markets, and Human Capital in a Developing Country," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 64(3), pages 311-335.
    18. Gary S. Becker & Nigel Tomes, 1994. "Human Capital and the Rise and Fall of Families," NBER Chapters, in: Human Capital: A Theoretical and Empirical Analysis with Special Reference to Education, Third Edition, pages 257-298, National Bureau of Economic Research, Inc.
    19. F. Rosati & M. Rossi, 2001. "Children's Working Hours, School Enrolment and Human Capital Accumulation: Evidence from Pakistan and Nicaragua," UCW Working Paper 8, Understanding Children's Work (UCW Programme).
    20. Jean-Marie Baland & James A. Robinson, 2000. "Is Child Labor Inefficient?," Journal of Political Economy, University of Chicago Press, vol. 108(4), pages 663-679, August.
    21. Dehejia, Rajeev H. & Gatti, Roberta, 2002. "Child labor : the role of income variability and access to credit in a cross-section of countries," Policy Research Working Paper Series 2767, The World Bank.
    22. David Card, 1994. "Earnings, Schooling, and Ability Revisited," Working Papers 710, Princeton University, Department of Economics, Industrial Relations Section..
    23. Rosenzweig, Mark R & Evenson, Robert E, 1977. "Fertility, Schooling, and the Economic Contribution of Children in Rural India: An Econometric Analysis," Econometrica, Econometric Society, vol. 45(5), pages 1065-1079, July.
    24. Alan B. Krueger, 1996. "Observations on International Labor Standards and Trade," NBER Working Papers 5632, National Bureau of Economic Research, Inc.
    25. Grootaert, Christiaan & Kanbur, Ravi, 1995. "Child labor : a review," Policy Research Working Paper Series 1454, The World Bank.
    26. Fortin, Bernard & Lacroix, Guy, 1997. "A Test of the Unitary and Collective Models of Household Labour Supply," Economic Journal, Royal Economic Society, vol. 107(443), pages 933-955, July.
    27. Geeta Gandhi Kingdon, 1998. "Does the labour market explain lower female schooling in India?," Journal of Development Studies, Taylor & Francis Journals, vol. 35(1), pages 39-65.
    28. Ranjan Ray, 2000. "Analysis of child labour in Peru and Pakistan: A comparative study," Journal of Population Economics, Springer;European Society for Population Economics, vol. 13(1), pages 3-19.
    29. Nelson, Charles R & Startz, Richard, 1990. "The Distribution of the Instrumental Variables Estimator and Its t-Ratio When the Instrument Is a Poor One," The Journal of Business, University of Chicago Press, vol. 63(1), pages 125-140, January.
    30. Alok Bhargava, 2006. "Identification and Panel Data Models with Endogenous Regressors," World Scientific Book Chapters, in: Econometrics, Statistics And Computational Approaches In Food And Health Sciences, chapter 3, pages 49-60, World Scientific Publishing Co. Pte. Ltd..
    31. Peter Jensen & Helena Skyt Nielsen, 1997. "Child labour or school attendance? Evidence from Zambia," Journal of Population Economics, Springer;European Society for Population Economics, vol. 10(4), pages 407-424.
    32. Alan B. Krueger & Andreas Mueller, 2011. "Job Search and Job Finding in a Period of Mass Unemployment: Evidence from High-Frequency Longitudinal Data," Working Papers 1295, Princeton University, Department of Economics, Center for Economic Policy Studies..
    33. Douglas Staiger & James H. Stock, 1997. "Instrumental Variables Regression with Weak Instruments," Econometrica, Econometric Society, vol. 65(3), pages 557-586, May.
    34. Pencavel, John, 1987. "Labor supply of men: A survey," Handbook of Labor Economics, in: O. Ashenfelter & R. Layard (ed.), Handbook of Labor Economics, edition 1, volume 1, chapter 1, pages 3-102, Elsevier.
    35. Skoufias, Emmanuel & Parker, Susan W., 2001. "Conditional cash transfers and their impact on child work and schooling," FCND briefs 123, International Food Policy Research Institute (IFPRI).
    36. Baland, J.M. & Robinson, J.A., 1998. "A Model of Child Labor," Papers 206, Notre-Dame de la Paix, Sciences Economiques et Sociales.
    37. Bhalotra, Sonia, 2002. "Parent Altruism," Royal Economic Society Annual Conference 2002 25, Royal Economic Society.
    38. Jere R. Behrman & Andrew D. Foster & Mark R. Rosenzweig & Prem Vashishtha, 1999. "Women's Schooling, Home Teaching, and Economic Growth," Journal of Political Economy, University of Chicago Press, vol. 107(4), pages 682-714, August.
    39. Eric V. Edmonds, 2004. "Does Illiquidity Alter Child Labor and Schooling Decisions? Evidence from Household Responses to Anticipated Cash Transfers in South Africa," NBER Working Papers 10265, National Bureau of Economic Research, Inc.
    40. Shahnaz Hamid, 1994. "A Micro Analysis of Urban Child Labour: Some Determinants of Labour and its Conditions," The Pakistan Development Review, Pakistan Institute of Development Economics, vol. 33(4), pages 1249-1271.
    41. Dehejia, Rajeev H. & Beegle, Kathleen & Gatti, Roberta, 2003. "Child labor, income shocks, and access to credit," Policy Research Working Paper Series 3075, The World Bank.
    42. George Psacharopoulos & Harry Anthony Patrinos, 1997. "Family size, schooling and child labor in Peru - An empirical analysis," Journal of Population Economics, Springer;European Society for Population Economics, vol. 10(4), pages 387-405.
    43. Ray, Ranjan, 2000. "Child Labor, Child Schooling, and Their Interaction with Adult Labor: Empirical Evidence for Peru and Pakistan," The World Bank Economic Review, World Bank, vol. 14(2), pages 347-367, May.
    44. Parsons, Donald O & Goldin, Claudia, 1989. "Parental Altruism and Self-Interest: Child Labor among Late Nineteenth-Century American Families," Economic Inquiry, Western Economic Association International, vol. 27(4), pages 637-659, October.
    45. Drusilla K. Brown & Alan V. Deardorff & Robert M Stern, 2001. "Child Labor: Theory, Evidence, and Policy," Working Papers 474, Research Seminar in International Economics, University of Michigan.
    46. Kaushik Basu, 2006. "Gender and Say: a Model of Household Behaviour with Endogenously Determined Balance of Power," Economic Journal, Royal Economic Society, vol. 116(511), pages 558-580, April.
    47. Douglas A. Galbi, 1997. "Child labor and the division of labor in the early English cotton mills," Journal of Population Economics, Springer;European Society for Population Economics, vol. 10(4), pages 357-375.
    48. Kaushik Basu & Zafiris Tzannatos, 2003. "The Global Child Labor Problem: What Do We Know and What Can We Do?," The World Bank Economic Review, World Bank, vol. 17(2), pages 147-173, December.
    49. Meghir, Costas & Phillips, David, 2008. "Labour Supply and Taxes," IZA Discussion Papers 3405, Institute of Labor Economics (IZA).
    50. Rajeev Dehejia & Roberta Gatti, 2002. "Child Labor: The Role of Income Variability and Access to Credit Across Countries," NBER Working Papers 9018, National Bureau of Economic Research, Inc.
    51. repec:bla:rdevec:v:4:y:2000:i:2:p:219-28 is not listed on IDEAS
    52. Case, Anne & Lin, I-Fen & McLanahan, Sara, 2000. "How Hungry Is the Selfish Gene?," Economic Journal, Royal Economic Society, vol. 110(466), pages 781-804, October.
    53. Basu, Kaushik & Van, Pham Hoang, 1998. "The Economics of Child Labor," American Economic Review, American Economic Association, vol. 88(3), pages 412-427, June.
    54. Alan Krueger, 1996. "Observations on International Labor Standards and Trade," Working Papers 741, Princeton University, Department of Economics, Industrial Relations Section..
    55. White, Halbert, 1980. "A Heteroskedasticity-Consistent Covariance Matrix Estimator and a Direct Test for Heteroskedasticity," Econometrica, Econometric Society, vol. 48(4), pages 817-838, May.
    56. Davidson, Russell & MacKinnon, James G., 1993. "Estimation and Inference in Econometrics," OUP Catalogue, Oxford University Press, number 9780195060119.
    57. Glewwe, P. & Jacoby, H., 1993. "Delayed Primary School Enrollment and Childhood Malnutrition in Ghana, an Economic Analysis," Papers 98, World Bank - Living Standards Measurement.
    58. Swaminathan, Madhura, 1998. "Economic growth and the persistence of child labor: Evidence from an Indian city," World Development, Elsevier, vol. 26(8), pages 1513-1528, August.
    59. Kniesner, Thomas J, 1976. "An Indirect Test of Complementarity in a Family Labor Supply Model," Econometrica, Econometric Society, vol. 44(4), pages 651-669, July.
    60. Ranjan, Priya, 1999. "An economic analysis of child labor," Economics Letters, Elsevier, vol. 64(1), pages 99-105, July.
    61. Card, David, 1988. "Emperical tests of labor-market equilibrium: An evaluation : A comment," Carnegie-Rochester Conference Series on Public Policy, Elsevier, vol. 28(1), pages 259-267, January.
    62. Martin Shubik, 2001. "On Understanding Money," World Economics, World Economics, 1 Ivory Square, Plantation Wharf, London, United Kingdom, SW11 3UE, vol. 2(1), pages 95-120, January.
    63. Christelle Dumas, 2007. "Why do parents make their children work? A test of the poverty hypothesis in rural areas of Burkina Faso," Oxford Economic Papers, Oxford University Press, vol. 59(2), pages 301-329, April.
    64. Bhalotra, Sonia & Heady, Chris, 2000. "Child farm labour: theory and evidence," LSE Research Online Documents on Economics 6654, London School of Economics and Political Science, LSE Library.
    65. Ravallion, Martin & Wodon, Quentin, 2000. "Does Child Labour Displace Schooling? Evidence on Behavioural Responses to an Enrollment Subsidy," Economic Journal, Royal Economic Society, vol. 110(462), pages 158-175, March.
    66. Jolliffe, Dean, 1997. "Whose education matters in the determination of household income," FCND discussion papers 39, International Food Policy Research Institute (IFPRI).
    67. Mroz, Thomas A, 1987. "The Sensitivity of an Empirical Model of Married Women's Hours of Work to Economic and Statistical Assumptions," Econometrica, Econometric Society, vol. 55(4), pages 765-799, July.
    68. John Shea, 1997. "Instrument Relevance in Multivariate Linear Models: A Simple Measure," The Review of Economics and Statistics, MIT Press, vol. 79(2), pages 348-352, May.
    69. Heckman, James J, 1974. "Shadow Prices, Market Wages, and Labor Supply," Econometrica, Econometric Society, vol. 42(4), pages 679-694, July.
    70. repec:fth:prinin:331 is not listed on IDEAS
    71. George Psacharopoulos, 1997. "Child labor versus educational attainment Some evidence from Latin America," Journal of Population Economics, Springer;European Society for Population Economics, vol. 10(4), pages 377-386.
    72. Nielsen, H.S., 1998. "Child Labor and School Attendance: Two Joint Decisions," Papers 98-15, Centre for Labour Market and Social Research, Danmark-.
    73. Sonia Bhalotra, 2004. "Parent Altruism, Cash Transfers and Child Poverty," Bristol Economics Discussion Papers 04/561, School of Economics, University of Bristol, UK.
    74. Sonia Bhalotra, 2003. "Child Labour in Africa," OECD Social, Employment and Migration Working Papers 4, OECD Publishing.
    75. Emerson, Patrick M & Souza, Andre Portela, 2003. "Is There a Child Labor Trap? Intergenerational Persistence of Child Labor in Brazil," Economic Development and Cultural Change, University of Chicago Press, vol. 51(2), pages 375-398, January.
    76. Mark R. Rosenzweig, 1980. "Neoclassical Theory and the Optimizing Peasant: An Econometric Analysis of Market Family Labor Supply in a Developing Country," The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 94(1), pages 31-55.
    77. repec:fth:prinin:362 is not listed on IDEAS
    78. Fortin, B. & Lacroix, G., 1993. "A Test of the Neoclassical and Collective Models of Household Labour Supply," Papers 9335, Laval - Recherche en Politique Economique.
    79. Sonia Bhalotra, and Zafiris Tzannatos, 2003. "Child labor : what have we learnt?," Social Protection Discussion Papers and Notes 27872, The World Bank.
    80. Barzel, Yoram & McDonald, Richard J, 1973. "Assets, Subsistence, and The Supply Curve of Labor," American Economic Review, American Economic Association, vol. 63(4), pages 621-633, September.
    81. James J. Heckman & Thomas E. Macurdy, 1980. "A Life Cycle Model of Female Labour Supply," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 47(1), pages 47-74.
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    More about this item

    Keywords

    Child labour; education; poverty; gender; intertemporal labour supply.;
    All these keywords.

    JEL classification:

    • D12 - Microeconomics - - Household Behavior - - - Consumer Economics: Empirical Analysis
    • J13 - Labor and Demographic Economics - - Demographic Economics - - - Fertility; Family Planning; Child Care; Children; Youth
    • J22 - Labor and Demographic Economics - - Demand and Supply of Labor - - - Time Allocation and Labor Supply
    • O12 - Economic Development, Innovation, Technological Change, and Growth - - Economic Development - - - Microeconomic Analyses of Economic Development

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