Economic growth and income inequality: Non-linearities and income level threshold effect.

DiMaria, Charles-Henri (2025): Economic growth and income inequality: Non-linearities and income level threshold effect.

Abstract

Despite the pioneering works of Kuznets and Kaldor in the mid-fifties, it was not until the nineties that economists began to thoroughly investigate whether income inequality is detrimental or conducive to growth. A brief survey of the literature does not yield a definitive conclusion. Some authors argue that inequality is beneficial, as higher-income populations are more likely to save and invest in innovative activities. Conversely, other authors contend that concentrating income in the hands of a few limits the number of potential investors, hinders the development of markets and industries with increasing returns, and may dis-incentivize investment in human capital. Since the mid-nineties, most empirical studies attempting to uncover a link between income inequality and growth have concluded that the relationship is predominantly negative. In this study, we reveal a more complex link, characterized by an inverted-U shape that is mostly negative and only applicable to countries with intermediate income per capita. For poor and rich countries, this link does not exist. We employ a panel threshold model approach, introducing income inequality in linear, quadratic, and cubic forms to allow for potential linear, U-shaped, inverted-U-shaped, and even more complex relationships between inequality and growth.

• Item Type: MPRA Paper
• Language: English
• Keywords: Income inequality, growth regression, panel threshold.
• Subjects: C - Mathematical and Quantitative Methods > C2 - Single Equation Models ; Single Variables > C23 - Panel Data Models ; Spatio-temporal Models; D - Microeconomics > D6 - Welfare Economics > D63 - Equity, Justice, Inequality, and Other Normative Criteria and Measurement; O - Economic Development, Innovation, Technological Change, and Growth > O4 - Economic Growth and Aggregate Productivity > O47 - Empirical Studies of Economic Growth ; Aggregate Productivity ; Cross-Country Output Convergence

References

Aghion, P. and Bolton, P., 1997. A theory of trickle-down growth and development. The review of economic studies, 64(2), pp.151-172.

Alesina, A. and Rodrik, D., 1994. Distributive politics and economic growth. The quarterly journal of economics, 109(2), pp.465-490.

Amarante, V., 2014. Revisiting inequality and growth: Evidence for developing countries. Growth and Change, 45(4), pp.571-589.

Assa, J., 2012. Inequality and growth re-examined. Technology and Investment, 3(1), pp.1-6.

Balcilar, M., Gupta, R., Ma, W. and Makena, P., 2021. Income inequality and economic growth: A re‐examination of theory and evidence. Review of Development Economics, 25(2), pp.737-757.

Banerjee, A.V. and Duflo, E., 2003. Inequality and growth: What can the data say?. Journal of economic growth, 8, pp.267-299.

Barro, R. J. Inequality and growth revisited. No. 11. ADB Working paper series on regional economic integration, 2008.

Bartak, J. and Jabłoński, Ł., 2020. Inequality and growth: What comes from the different inequality measures?. Bulletin of Economic Research, 72(2), pp.185-212.

Benabou, R., 1996. Inequality and growth. NBER macroeconomics annual, 11, pp.11-74.

Berg, A., Ostry, J.D., Tsangarides, C.G. and Yakhshilikov, Y., 2018. Redistribution, inequality, and growth: new evidence. Journal of economic growth, 23, pp.259-305.

Bergh, A. and Henrekson, M., 2011. Government size and growth: a survey and interpretation of the evidence. Journal of Economic Surveys, 25(5), pp.872-897.

Blotevogel, R., Imamoglu, E., Moriyama, K. and Sarr, B., 2020. Measuring income inequality and implications for economic transmission channels (No. 2020/164). International Monetary Fund.

Bourguignon, F., 1981. Pareto superiority of unegalitarian equilibria in Stiglitz'model of wealth distribution with convex saving function. Econometrica: Journal of the Econometric Society, pp.1469-1475.

Brueckner, M. and Lederman, D., 2018. Inequality and economic growth: the role of initial income. Journal of Economic Growth, 23, pp.341-366.

Castelló-Climent, A., 2010. Inequality and growth in advanced economies: an empirical investigation. The Journal of Economic Inequality, 8, pp.293-321.

Cerra V., Lama, R. and Loayza, N., 2021. Links Between Growth, Inequality, and Poverty: A Survey. IMF Working Paper Institute for Capacity Development.

Chambers, D. and Krause, A., 2010. Is the relationship between inequality and growth affected by physical and human capital accumulation?. The Journal of Economic Inequality, 8, pp.153-172.

Chan, K.-S. "Consistency and limiting distribution of the least squares estimator of a threshold autoregressive model." The annals of statistics (1993): 520-533.

Chen, B.L., 2003. An inverted-U relationship between inequality and long-run growth. Economics Letters, 78(2), pp.205-212.

Clarke, G.R., 1995. More evidence on income distribution and growth. Journal of development Economics, 47(2), pp.403-427.

Dahan, M. and Tsiddon, D., 1998. Demographic transition, income distribution, and economic growth. Journal of Economic growth, 3(1), pp.29-52.

Deininger, K. and Squire, L., 1998. New ways of looking at old issues: inequality and growth. Journal of development economics, 57(2), pp.259-287.

De La Croix, D. and Doepke, M., 2003. Inequality and growth: why differential fertility matters. American Economic Review, 93(4), pp.1091-1113.

Dollar, D., 1992. Outward-oriented developing economies really do grow more rapidly: evidence from 95 LDCs, 1976-1985. Economic development and cultural change, 40(3), pp.523-544.

Easterly, W., 2007. Inequality does cause underdevelopment: Insights from a new instrument. Journal of development economics, 84(2), pp.755-776.

Ehrhart, C., 2009. The effects on inequality on growth: A survey of the theoretical and empirical literature. ECINEQ working paper series.

Forbes, K.J., 2000. A reassessment of the relationship between inequality and growth. American economic review, 90(4), pp.869-887.

Frankel, J., and Romer, D., 2000. Does trade cause growth? American Economic Review, 89(3), pp.379–399.

Galor, O. and Tsiddon, D., 1997. Technological progress, mobility, and economic growth. The American Economic Review, pp.363-382.

Galor, O. and Weil, D.N., 1996. The Gender Gap, Fertility and Growth. American Economic Review, 86(3), pp.p374-387.

Galor, O. and Zeira, J., 1993. Income distribution and macroeconomics. The review of economic studies, 60(1), pp.35-52.

Glaeser, E., Scheinkman, J. and Shleifer, A., 2003. The injustice of inequality. Journal of Monetary Economics, 50(1), pp.199-222.

Hansen, B.E. (1996). Inference when a nuisance parameter is not identified under the null hypothesis. Econometrica: Journal of the econometric society, 413-430.

Hansen, B. E. (1999). Threshold effects in non-dynamic panels: Estimation, testing, and inference. Journal of econometrics, 93(2), 345-368.

Herzer, D. and Vollmer, S., 2012. Inequality and growth: evidence from panel cointegration. The Journal of Economic Inequality, 10, pp.489-503.

Kaldor, N., 1957. A model of economic growth. The economic journal, 67(268), pp.591-624.

Knowles, S., 2005. Inequality and economic growth: The empirical relationship reconsidered in the light of comparable data. The Journal of Development Studies, 41(1), pp.135-159.

Kuznets, S., 1955. Economic growth and income inequality. American economic association. The American Economic Review, 45(1), pp.1-28.

Lee, W. and Roemer, J.E., 1998. Income distribution, redistributive politics, and economic growth. Journal of Economic Growth, 3(3), pp.217-240.

Levin, A., Lin, C.F. and Chu, C.S.J., 2002. Unit root tests in panel data: asymptotic and finite-sample properties. Journal of econometrics, 108(1), pp.1-24.

Li, H. and Zou, H.F., 1998. Income inequality is not harmful for growth: theory and evidence. Review of development economics, 2(3), pp.318-334.

Lin, Y.C. and Yeh, C.C., 2009. Joint determinations of inequality and growth. Economics Letters, 103(3), pp.163-166.

Maddala, G.S. and Wu, S., 1999. A comparative study of unit root tests with panel data and a new simple test. Oxford Bulletin of Economics and statistics, 61(S1), pp.631-652.

Mo, P.H., 2000. Income inequality and economic growth. Kyklos, 53(3), pp.293-315.

Murphy, K.M., Shleifer, A. and Vishny, R., 1989. Income distribution, market size, and industrialization. The Quarterly Journal of Economics, 104(3), pp.537-564.

Naguib, C., 2015. The relationship between inequality and GDP growth: An empirical approach. LIS Working Paper Series, No. 631, Luxembourg Income Study (LIS), Luxembourg

Naguib, C., 2017. The relationship between inequality and growth: Evidence from new data. Swiss Journal of Economics and Statistics, 153, pp.183-225.

Nolan, B., Richiardi, M.G. and Valenzuela, L., 2019. The drivers of income inequality in rich countries. Journal of Economic Surveys, 33(4), pp.1285-1324.

Perotti, R., 1993. Political equilibrium, income distribution, and growth. The Review of Economic Studies, 60(4), pp.755-776.

Perotti, R., 1996. Growth, income distribution, and democracy: What the data say. Journal of Economic growth, 1, pp.149-187.

Persson, T. and Tabellini, G., 1991. ls lnequality Harmful for Growth. American Economic Review (June 1994), pp.600-621.

Pesaran, M.H., 2007. A simple panel unit root test in the presence of cross‐section dependence. Journal of applied econometrics, 22(2), pp.265-312.

Piketty, T., 1997. The dynamics of the wealth distribution and the interest rate with credit rationing. The Review of Economic Studies, 64(2), pp.173-189.

Piketty, T., 2000. Theories of persistent inequality and intergenerational mobility. Handbook of income distribution, 1, pp.429-476.

Sachs, J.D., Warner, A., Åslund, A. and Fischer, S., 1995. Economic reform and the process of global integration. Brookings papers on economic activity, 1995(1), pp.1-118.

Saint-Paul G, Verdier T. Education, democracy and growth. Journal of development Economics. 1993 Dec 1;42(2):399-407.

Sukiassyan, G., 2007. Inequality and growth: What does the transition economy data say?. Journal of comparative economics, 35(1), pp.35-56.

Zhang, L. and Lewsey, J., 2024. Comparing the performance of two-stage residual inclusion methods when using physician's prescribing preference as an instrumental variable: unmeasured confounding and noncollapsibility. Journal of Comparative Effectiveness Research, 13(5), p.e230085.