Investigating the spatial spillover effect of institutional factors on reducing income inequality

Volume 23, Issue 2 - Serial Number 89
Vol. 23, No. 2, Summer 2026
Summer 2026
Pages 70-103

Document Type : Research Paper

Authors

1 * Master of Economics, Department of Economics, Faculty of Economics and Social Sciences, University of kurdstan, sanandaj, Iran.

2 Assistant Professor of Economics, Department of Economics, Faculty of Economics and Social Sciences, University of kurdstan, sanandaj, Iran

3 Assistant Professor, Department of Economics, Faculty of Humanities and Social Sciences, University of Kurdistan, Iran

Abstract
EXTENDED ABSTRACT
 
INTRODUCTION:
In recent years, the concept of inequality has expanded significantly, and various approaches to addressing it have also increased. Despite the economic growth achieved by many countries, inequality has not declined substantially and, in some cases, has even intensified. Therefore, identifying the factors that can effectively reduce inequality has always been of great interest to economists and policymakers. Among these factors, institutional quality and economic growth play key roles. Effective institutions such as transparent and efficient governance, strong property rights, and the rule of law can make a significant contribution to reducing inequality.
Recent empirical studies support this view. For instance, Aghaei, Rezaei, and Ahmadi (2023), in an article published in the Quantitative Economics Quarterly, found that improving institutional quality and good governance has a significant negative impact on income inequality in developing countries. The results indicated that the rule of law and government effectiveness were the most influential indicators in reducing inequality. Similarly, Ansari and Jafari (2022), using a spatial econometric approach, analyzed the effects of economic growth and human capital on income inequality in selected Asian countries. Their findings revealed a positive spatial spillover effect, meaning that inequality in one country can affect neighboring countries through economic and regional linkages.
Recent empirical evidence also indicates that financial inclusion can have a negative and significant effect on income inequality, while its spatial spillover effects are significant under some spatial econometric specifications (Pirzadi et al., 2024). Moreover, recent spatial research emphasizes the existence of interregional spillovers and the transmission of economic policies and developments from one region to neighboring regions (Khodavardi Samani et al., 2025).
According to the World Bank (2023), global inequality has been rising, hindering the full recovery of economies from the devastating effects of the COVID-19 pandemic, with poorer nations suffering the most. Increasing inequality has broad economic, social, and political consequences. Data from the World Inequality Database show that between 1980 and 2016, the top 1% of the world’s population increased their income by 27%, while the bottom 50% saw only a 12% increase. The Middle East and West Asia are now among the most unequal regions in the world.
Therefore, examining the impact of institutional factors on inequality reduction in selected Asian countries during 1990–2020, using a spatial econometric approach, can provide new insights into how geographical proximity and spatial interdependence influence inequality dynamics across nations.
 
METHODOLOGY:
In this research, the research method is analytical and econometric. The data of this research has been collected from the World Bank, Macro Trends website and OECD website. STAT 17 software was used to estimate the model. Because in panel data, by combining data in two dimensions (time and place), it is possible to check data changes, and at the same time, the problem of colinearity is also reduced. Panel data and panel analysis allow the study of more complex behavioral models. The model used in this research is as Equation  1 follows:
 
Equation  1




 


     




 
which by expanding the institutional variables we have in Equation  2:
 
Equation  2
 




 


      




Spatial effects in calculations are factors that are related to the location of variables. The first factor is the spatial dependence or autocorrelation between the sample data observations at different points and the second factor is the spatial structure or heterogeneity created by the model relationships for movement in the plane. Coordinates change with sample data. To detect the spatiality of the data, it is necessary to perform spatial detection tests, but note that performing this test is a weakness in complex time series where it is not possible to detect spatial correlation. In this study, as stated, there are several countries that have a geographical connection with the quantifiable index, and these countries selected in this research have proximity to each other. The weight matrix is ​​of proximity type Stata software is used to introduce the model, which uses a new method to estimate the spatial econometric model of the panel data type. With this method, we can consider a set of fixed and random models for the model, and using the Hausman test, the best model is selected from SAR, SDM, SAC, SEM, and GSPRE models. With the estimates made, the SAC model was selected and the F-Limer statistic was used to test the panel data and consolidated data. Different tests can be used to select the fixed and random effects model. Due to the spatial dependence in the research, the modeling of this research was done in the space dimension, for this reason, we use the SAC spatial panel model. To choose between fixed and random effects, the Hausman test was performed and the obtained results show that fixed effects are more efficient than random effects, so we will examine the fixed effects.
 
FINDINGS:
The research results show that institutional factors have positive and significant spatial effects both directly and indirectly on inequality in the studied countries. Economic growth, government stability, corruption control, democracy index and financial development have a positive and significant effect on reducing inequality.
 
CONCLUSION:
The quality of institutional factors improves the performance of the government by influencing the areas of freedom of expression and accountability of the government. Economic growth can create prosperity and opportunity. Strong growth creates new job opportunities that raise the incomes of the poor and increase their incentives to invest in their children. Economic growth increases the income of the entire society and creates more jobs, income and opportunities that can be redistributed. Also, financial development makes low-income people have access to financial and credit resources. An efficient financial system can direct investment to the best path. The research results confirm the effects of effective financial development in reducing inequality.

Keywords

Subjects
Acemoglu, D. Johnson, S. & Robinson, J.A. (2005). Institutions as a fundamental cause of long-run growth. Handbook of economic growth, 1, 385-472.
Adeleye,B.N.Gershon,O. Ogundipe, A. Owolabi, O. Ogunrinola, I. & Adediran, O. (2020). Comparative investigation of the growth-poverty-inequality trilemma in Sub-Saharan Africa and Latin American and Caribbean Countries. Heliyon, 6(12).
Ali, Omer, William A. Darity Jr. Avra Janz, and Marta Sánchez. 2021. "The Association between Wealth Inequality and Socioeconomic Outcomes. AEA Papers and Proceedings, 111: 211-15.
Alvaredo, F. L Assouad and T Piketty (2017). Measuring inequality in the Middle East, 1990-2016: The world’s most unequal region. WID.world Working Paper no 2017/15.
Andres, A. R. & Ramlogan-Dobson, C. (2011). Is corruption really bad for inequality? Evidence from Latin America. Journal of Development Studies, 47(7), 959-976.
Appiah-Otoo, I. Chen, X. Song, N. & Dumor, K. (2022). Financial development, institutional improvement, poverty reduction: The multiple challenges in West Africa. Journal of Policy Modeling, 44(6), 1296-1312.
Assouad, L. L Chancel & M Morgan (2018).Extreme inequality: Evidence from Brazil, India, the Middle East and South Africa. American Economic Association Papers & Proceedings.
Ayubi, Shabir Ahmad (2021). The relationship between institutional quality and economic growth in Afghanistan. Masters. University of Sistan and Baluchestan(In Persian).
 Azizi Zahra, Berari Asieh and Ahmadpour Kechu Ali (2021). The effect of institutional quality on financial development (case study: developing countries in the Eurasian region). Publication: Economic Studies and Policies. Volume 8. Number 1(15). Page 247-274(In Persian).
Batuo, M. E. & Asongu, S. A. (2015). The impact of liberalisation policies on income inequality in African countries. Journal of Economic Studies, 42(1), 68-100.
 Behnejad, Saideh (2017). The role of institutional conditions in the impact of economic growth on poverty and income inequality. Masters. Mashhad Ferdowsi University)In Persian(.
Berg, A. Ostry, J. D. Tsangarides, C. G. & Yakhshilikov, Y. (2018). Redistribution, inequality, and growth: new evidence. Journal of Economic Growth, 23, 259-305.
Bobzien, L. Income Inequality and Political Trust: Do Fairness Perceptions Matter? Soc Indic Res 169, 505–528 (2023). https://doi.org/10.1007/s11205-023-03168-9
Brady, David, Agnes Blome, and Hanna Kleider, 'How Politics and Institutions Shape Poverty and Inequality', in David Brady, and Linda M. Burton (eds), The Oxford Handbook of the Social Science of Poverty, Oxford Handbooks (2016; online edn, Oxford Academic, 5 Apr. 2017), https://doi.org/10.1093/oxfordhb/9780199914050.
Chong, A. & Calderon, C. (2000). Institutional quality and income distribution. Economic Development and Cultural Change, 48(4), 761-786.
Chong, A. & Gradstein, M. (2007). Inequality and institutions. The review of Economics and Statistics, 89(3), 454-465.
Coccia, M. (2021). How a Good Governance of Institutions Can Reduce Poverty and Inequality in Society? In: Faghih, N. Samadi, A.H. (eds) Legal-Economic Institutions, Entrepreneurship, and Management. Contributions to Management Science. Springer,. https://doi.org/10.1007/978-3-030-60978-8_4.
Coccia, M. (2021). How a good governance of institutions can reduce poverty and inequality in society? Legal-Economic Institutions, Entrepreneurship, and Management: Perspectives on the Dynamics of Institutional Change from Emerging Markets, 65-94. DOI: 10.1111/1467-8454.12322
Eunni, R. V. (2010). Institutional Environments For Entrepreneurship In Emerging Economies: Brazil Vs. Mexico. World.J. Management, 2(1), 1-18
Gholizadeh & aelmi(2023), Institutional quality and tax evasion in Iran. Quantitative Economics Research Quarterly, 20(4), 38-86. doi: 10.22055/jqe.2021.35404.2283.
Growth and Development Report. (2008). The growth report; strategies for sustained growth and inclusive development. The International Bank for Reconstruction and Development, The World Bank.
Gupta, S. Davoodi, H. & Alonso-Terme, R. (1998). Does corruption affect income inequality and poverty, IMF Working Paper. pp, 76–98.
Hacibedel, B. Mandon, P. Muthoora, P. et al. Inequality, growth fluctuations, and employment. Empir Econ 66, 587–622 (2024). https://doi.org/10.1007/s00181-023-02476-w.
Hodgson, G.M. (2006). What Are Institutions. J. Economic issues, xl(1):Pp 1-25.
Hosseini, Mohaddeseh, Ahmadi Shadmehri, Mohammad Taher and Gorjipour, Mohammad Javad. (2021). Investigating the effect of democracy on the relationship between economic growth and income inequality in Iran. Quarterly Journal of Quantitative Economics, 18(1), 1-16. (In Persian(. doi: 10.22055/jqe.2020.29003.2058.
Jones, E. L. (1981). The European miracle: Environments, economies and geopolitics in the history of Europe and Asia. Cambridge: Cambridge University Press.
Keefer, P. & Knack, S. (1997). Why don't poor countries catch up? A cross‐national test of an institutional explanation. Economic inquiry, 35(3), 590-602
Knack, S. & Keefer, P. (1997). Why don’t poor countries catch up A cross national test of an institutional explanation. Economic Inquiry, 35, 590–602.
Khodavardi Samani, M., Alizadeh, S., & Shaghaghi Shahri, V. (2025). Spatial spillover of fiscal decentralization on social welfare in Iranian provinces during 1385–1397: A spatial econometric approach. Quarterly Journal of Quantitative Economics, 22(2), 82–124. doi: 10.22055/jqe.2023.40959.2490.
Labidi MA, Ochi A, Saidi Y. (2022). Extreme poverty, economic growth and income inequality trilogy in sub-Saharan Africa and South Asia: A GMM panel VAR approach. Research Square.
Lucas Chancel & Thomas Piketty. (2021). Global Income Inequality, 1820–2020: the Persistence and Mutation of Extreme Inequality [Global Inequality of Hourly Income, 1980–2020]. Journal of the European Economic Association, European Economic Association, vol. 19(6), pages 3025-3062.
Mdingi, K. & Ho, S. Y. (2023). Income inequality and economic growth: An empirical investigation in South Africa. Cogent Economics & Finance, 11(2). https://doi.org/10.1080/23322039.2023.2230027
Moradi, Fatemeh, Jafari, Mohammad and Fattahi, Shahram. (2023). The effect of good governance on income inequality in selected developing and developed countries; with emphasis on corruption control. Quarterly Journal of Quantitative Economics, 20(3), 110-135. (In Persian(.doi: 10.22055/jqe.2021.37420.2374.
Mubarak Asghar, Hejbar Kiani Kambiz, Mimarnjad Abbas, Pikarjo Kambiz (2017). Studying the effect of institutional quality and human capital on economic growth (case study: developing and developed countries). Publication: Planning and Budget. Volume 23. Number 1. Page 117-146 (In Persian(.
Nik Pesian, Vahid, & Shahbazi, Kiyomarth. (2023). Spatial analysis of the effect of terrorism on the attraction of foreign direct investment in the Middle East. Quantitative Economics Research Quarterly, 20(2), 129-164. doi: 10.22055/jqe.2022.37973.239.
North, D. C. (1981). Structure and change in economic history. Norton & Co.
Ongo Nkoa, B.E. Song, J.S. Does Institutional Quality increase inequalities in Africa? J Knowl Econ 13, 1896–1927 (2022). https://doi.org/10.1007/s13132-021-00771-4
Ostry, Jonathan D. Loungani, P. & Berg, A. (2018). Confronting inequality: How societies can choose inclusive growth. Columbia University Press.
Ouechtati, I. Financial Inclusion, Institutional Quality, and Inequality: an Empirical Analysis. J Knowl Econ 14, 620–644 (2023). https://doi.org/10.1007/s13132-022-00909-y.
Panagariya, A. (2010). Sortir de la pauvreté. Finances & Développement, 47(3), 22–23.
Perotti, R. (1996). “Growth, Income Distribution and Democracy: What the Data Say”, Journal of Economic Growth, 1(2):149–187
Pirzadi, M., Soufi Majidpour, M., & Mahmoudzadeh, M. (2024). Local effects and spatial spillovers of financial inclusion on income inequality: An interprovincial analysis. Quarterly Journal of Quantitative Economics. doi: 10.22055/jqe.2019.26401.1899.
Rodrik, D. (2007). Growth building jobs and prosperity in developing countries. Departement for International Development, 1-25.
Sawadogo, R. & Semedo, G. (2021). Financial inclusion, income inequality, and institutions in sub-Saharan Africa: Identifying cross-country inequality regimes. International Economics, 167, 15-28.
Szczepaniak, M. Geise, A. & Bariyah, N. (2022). Impact of institutional determinants on income inequalities in Indonesia during the Era Reformasi. Journal of Asian Economics, 82, 101526.
Tebaldi, E. & Mohan, R. (2010). Institutions and poverty. The journal of development studies, 46(6), 1047-1066.
Uzar, Umut. 2023. "Income Inequality, Institutions, and Freedom of the Press: Potential Mechanisms and Evidence" Sustainability 15, no. 17: 12927. https://doi.org/10.3390/su151712927.
Williams, C. C. & Schneider, F. (2016). Measuring the Global Shadow Economy: the prevalence of informal work and labour. Edward Elgar Publishing.
World Bank. (2023). The World Bank Annual Report
Zhang, R. & Naceur, S. B. (2019). Financial development, inequality, and poverty: Some international evidence. International Review of Economics & Finance, 61, 1-16.
 
  • Receive Date 05 May 2024
  • Revise Date 12 September 2024
  • Accept Date 04 April 2025
  • First Publish Date 21 January 2026
  • Publish Date 23 August 2026