Distributional Comparisons Using the Gini Inequality Measure

This article is aimed at undergraduate and graduate economics students, as well as public sector economists, who are interested in inequality measurement. It examines the use of the Gini inequality measure to compare income distributions. The implicit distributional value judgements are made explicit, via the use of a particular form of Social Welfare Function. Emphasis is given to the interpretation of changes in inequality.     

Averaging Income Distributions

Various inequality and social welfare measures often depend heavily on the choice of a distribution of income. Picking a distribution that best fits the data involves throwing away information and does not allow for the fact that a wrong choice can be made. Instead, Bayesian model averaging utilizes a weighted average of the results from a number of income distributions, with each weight given by the probability that a distribution is ‘correct’. In this study, prior densities are placed on mean income, the mode of income and the Gini coefficient for Australian income units with one parent (1997–8). Then, using grouped sample data on incomes, posterior densities for the mean and mode of income and the Gini coefficient are derived for a variety of income distributions. The model‐averaged results from these income distributions are obtained.     

Income Inequality in Rural China: Regression-based Decomposition Using Household Data

A considerable literature exists on the measurement of income inequality in China and its increasing trend. Much less is known about the driving forces of this trend and their quantitative contributions. Conventional decompositions, by factor components or by population subgroups, provide only limited information on the determinants of income inequality. This paper represents an early attempt to apply the regression‐based decomposition framework to the study of inequality accounting in rural China, using household‐level data. It is found that geography has been the dominant factor but is becoming less important in explaining total inequality. Capital input emerges as a most significant determinant of income inequality. Farming structure is more important than labor and other inputs in contributing to income inequality across households.     

Income Mobility and Income Inequality in Rural China

The economic literature has argued for a long time that income mobility could attenuate the degree of cross-sectional inequality by offering people opportunities to improve their socio-economic position. Using the longitudinal data from the China Health and Nutrition Survey (CHNS) from 1989 to 2011, we measure income mobility as the degree to which longer-term incomes are distributed more or less equally than yearly income. Five main results are emphasized. First, there is strong income mobility in rural China that partly offsets yearly income inequality. Second, income mobility has decreased since the 2000s, indicating that income distribution is becoming more rigid. Third, mobility is mainly associated with transitory income fluctuations, particularly in the two tails of the distribution. Fourth, income mobility has an equalizing effect on income distribution. Fifth, we show that non-agricultural income mobility has substantially increased over the period and that its equalizing nature has also recently increased. While the development of the non-agriculture sector in rural China was a crucial factor in explaining the increase in rural inequality until the mid-2000s, we suggest that the large-scale generalisation of such non-agricultural opportunities partly accounts for the decline in rural inequality observed since the mid-2000s.     

Sources of Inequality: Measuring the Contributions of Income Sources to Rising Family Income Inequality

We develop a simulation method for measuring the impact of changes in the distributions of the main income sources on growth in family income inequality. We simulate the entire distribution of family income under the counterfactual, “What if the distribution of each source had not changed?” The simulation method allows us to evaluate the impact of changes at any point in the distribution as well as with multiple measures of inequality. We incorporate married‐couple and single‐person families, appropriately accounting for changes in the proportion married. We apply the simulation method to investigate the impact of changes in male earnings, female earnings, and capital income on the distribution of family income in the United States between 1969 and 1999. We find that changes in the distribution of male earnings account for more of the growth in family income inequality than do changes in any other source of income. Changes in the distribution of female earnings have reduced family income inequality.     

Income Inequality and Technological Adoption

We relate technological adoption (of different technologies) with income inequality. In the process, we discover that some technologies, such as aviation, cell phones, electric production, internet, telephone, and TV, are skill-complementary in raising inequality. We construct standardized indexes of skill-complementary technological adoption for modern information and communication technologies (ICT), older ICT, production and transport technologies. We find strong evidence that older ICT and transport technologies (and less frequently modern ICT) tend to increase inequality. Additionally, we discover that results are much stronger in rich countries than in poor ones. Our results are quite robust to a series of changes in specifications, estimators, samples, and measurement of technology adoption. These results may bring insights into the design of incentive schemes for technology adoption.     

Measuring Income Inequality in Euroland

In this paper we propose an aggregate measure of income inequality for the founding countries of the European Monetary Union. Applying the methodology of the Theil index we are able to derive a measure for Euroland as a whole by using complementary data from the European Community Household Panel and the Luxembourg Income Study. The property of additive decomposability allows us to determine each country's contribution as well as that of each demographic group to overall income inequality. In addition the impact of government transfers on this inequality measure is assessed.     

Oil Abundance and Income Inequality

The paper empirically investigates the impact of natural resource abundance, in particular oil, on income disparities. It employs common correlated effects pooled mean group methodology for estimation to account for the cross-country heterogeneity and cross-section dependence in the oil-inequality nexus. In a sample of developed and developing countries, we find that oil abundance as well as oil dependence reduce income inequality. This inequality-reducing effect is highly likely to operate from better education attainments and improved health status due to oil booms.     

宏观审慎政策与收入不平等

借助世代交替模型,得到宏观审慎政策影响收入不平等的理论机制,接着基于2000—2018年59国的非平衡面板数据,分析宏观审慎政策对收入不平等的影响。实证结果表明:(1)住房贷款价值比(LTV)上限与基尼系数呈负相关关系,说明实行降低LTV上限的宏观审慎政策对居民收入分配差距具有扩大作用,且扩大作用在新兴市场国家更为显著。(2)当LTV上限值较低时,降低LTV上限进一步扩大了收入不平等程度;相反,当LTV值较高时,降低LTV上限却减小了收入不平等程度,宏观审慎工具的政策效果呈现异质性特征。(3)将降低LTV上限的宏观审慎政策替换为提高存款准备金率等政策后,实证结论基本不变。实证结果在不同收入不平等变量、不同虚拟变量和不同面板模型下均表现出高度稳健性。对于我国而言,中国人民银行在制定宏观审慎政策时,应考虑政策的收入再分配效应,从而在确保政策有效性的同时,兼顾政策公平性。     

Income Inequality in Malaysia*

The objective of this paper is to examine the changes in Malaysian income distribution during the last three and a half decades and the reasons for the changes. It was found that the Gini ratio for Malaysia peaked in 1976 and fell thereafter to 1990. However, inequality seems to reverse its direction since then. Policies that could explain the changes in income distribution include the promotion of export‐oriented industrialization, education, and training, and the restructuring of equity ownership and assistance in asset accumulation. While the various other redistributive measures in the form of rural development helped in poverty eradication, their effectiveness in redistribution needs to be improved. Several hypotheses have been forwarded to explain the widening of income inequality after 1990. These include the difference in the growth rates of incomes of the rural and urban areas, trade and globalization, and impediments to the process of internal migration.     

Market Demand Elasticity and Income Inequality

This paper deals with the analysis of the relation between aggregate demand for a consumption good and the distribution of income across consumers. We obtain sufficient conditions under which changes in income inequality lead to an increase or decrease in the market demand elasticities. The conditions are satisfied for individual demand functions commonly used in economic models, in particular, for the typical demand functions on luxury goods and necessities. An earlier version of this paper was titled “Market demand elasticity, equilibrium stability and income inequality”. The authors are grateful to an anonymous referee, Aydin Cecen and Herbert Scarf for helpful comments and suggestions. R. Ibragimov gratefully acknowledges the financial support from the Yale Graduate Fellowship and the Cowles Foundation Prize.     

International Trade and Income Inequality*

We propose a simple theory that shows a mechanism through which international trade entails wage and job polarization. We consider two countries in which individuals with different abilities work either as knowledge workers, who develop differentiated products, or as production workers, who engage in production. In equilibrium, ex ante symmetric firms attract knowledge workers with different abilities, and this creates firm heterogeneity in product quality. Market integration disproportionately benefits firms that produce high-quality products. This winner-take-all trend of product markets causes a war for talents, which exacerbates income inequality within the countries and leads to labor-market polarization.     

Consumption and Income Inequality in Australia

Consumption may be a more appropriate measure of household well-being than income or earnings. Using four ABS Household Expenditures Surveys collected between 1975 and 1993, we compare trends in consumption and income inequality among Australian households. We find that consumption is much more equal than income. While there were significant increases in both income and consumption inequality, consumption inequality rose by much less. One interpretation of the results is that some income inequality in Australia reflects transitory fluctuations which households can smooth,'and that part of the growth in income inequality reflects an increase in these transitory fluctuations.     

收入不平等与中美经常项目失衡

本文建立一个开放经济环境的动态随机一般均衡模型,分析了收入不平等对经常项目的影响。数值模拟的结果表明:收入不平等可以通过国内消费需求、低收入阶层贷款和高收入阶层持有国外债券三个途径实现对经常项目的影响。长期内,收入不平等改善能够提高国内总需求,减少低收入阶层贷款和高收入阶层的国外债券持有量;短期内,收入不平等改善会降低中国低收入阶层消费,促进美国低收入阶层消费增加;收入不平等改善会减少中国经常项目顺差,而改善美国经常项目顺差,金融深化则会放大其作用幅度。本文结论显示,维持合理的收入分配以及适度的金融自由化水平有助于我国经常项目再平衡。     

个税改革、收入不平等与社会福利

2005年以来,历次中国个税改革均以提高免征额和调整税率表为主要内容,上述改革措施的分配效应一直存在争议.文章通过建立一个能体现个税累进性与税负归宿的新凯恩斯动态随机一般均衡模型,分解并模拟了提高免征额和增加税率累进幅度所导致的分配效应.结果表明:(1)提高免征额扩大了税前收入不平等的波动,恶化了宽松货币政策等外生冲击下的初次分配.此外,免征额的提高削弱了累进税率对收入初次分配的调节能力.(2)在就业扩张过程中,提高免征额所带来的税负归宿变化改善了税后收入不平等,而且在免征额提升后,税率累进幅度的提高能进一步改善收入再分配.当然,个税改革的初次分配效应和再分配效应均具有状态依存特征,在就业与劳动收入下降时会带来相反的分配效应.(3)提高免征额会导致更大的福利损失,并削弱累进税率对福利损失的抑制作用.