The Journal of Academic Science: The Relationship Between Income Inequality and Economic Growth
The Journal of Academic Science: The Relationship Between Income Inequality and Economic Growth
Saipudin
Faculty of Economic and Bussiness, Universitas Lambung Mangkurat, Indonesia
Email : saipudin.1986ulm@gmail.com
ABSTRACT
KEY W O R D S
The relationship between income inequality and economic growth has long been a
Income Inequality, subject of intense academic debate, with varying perspectives emerging from
Economic Growth, different theoretical and empirical studies. This article delves into the complexities of
Kuznets Curve, this relationship, exploring how income inequality can both positively and negatively
Developing Economies, impact economic growth, depending on the context. Theoretical perspectives range
from the classical Kuznets Curve, which posits that inequality initially increases with
Institutional
economic growth before eventually declining, to more contemporary views that
Frameworks highlight the risks of excessive inequality, particularly in developing economies.
Empirical evidence from developed and developing countries further underscores the
nuanced nature of this relationship. In developed economies, income inequality may
sometimes promote growth by incentivizing investment and innovation, provided
there are strong institutions to mitigate potential downsides. Conversely, in
developing economies, high levels of inequality often inhibit growth by restricting
access to education, healthcare, and other essential services, thus limiting human
capital development. The study also emphasizes the critical role of institutions and
policy interventions in shaping the relationship between income inequality and
economic growth. Effective governance, progressive taxation, and investment in
social infrastructure are highlighted as key strategies to balance growth with equity.
The findings suggest that while some inequality might be necessary to spur economic
progress, excessive inequality poses significant threats to long-term sustainable
development. The article concludes by advocating for a balanced policy approach that
promotes inclusive growth and ensures that the benefits of economic expansion are
shared more broadly across society.
The purpose of this study is to provide a more Data collection was conducted through
nuanced understanding of the relationship systematic searches in academic databases
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such as Google Scholar, JSTOR, and (Nowell, Norris, White, & Moules, 2017).
ScienceDirect, using keywords related to
income inequality, economic growth, and their
In conclusion, this study's methodological
interrelationship. The search was refined by
approach—grounded in a literature review with
applying inclusion and exclusion criteria,
thematic analysis—provides a robust
focusing on studies published within the last
framework for examining the complex
two decades to ensure the relevance and
relationship between income inequality and
timeliness of the findings. Additionally,
economic growth. By synthesizing existing
seminal works that have significantly shaped
research, the study aims to offer new insights
the discourse were also included, regardless of
and contribute to the ongoing scholarly debate
their publication date (Kitchenham, 2004).
on how these two variables interact.
For data analysis, the study adopts a thematic 3. Result and Discussion
analysis approach, which involves identifying,
analyzing, and reporting patterns or themes Below is a table of the literature review findings
within the literature (Braun & Clarke, 2006). related to the relationship between income
Thematic analysis is particularly effective in inequality and economic growth. This table
qualitative research as it allows for a detailed summarizes key studies, their methodologies,
and the main findings.
examination of recurring themes and concepts
across different studies, providing insights into
the prevailing narratives and identifying gaps
in the literature. The analysis process involved
coding the data, grouping similar concepts
together, and interpreting the findings in the
context of existing theories and frameworks
Author(s)
Title Methodology Key Findings
and Year
Proposed the Kuznets Curve, suggesting that income inequality
Kuznets, S. Economic Growth and Theoretical
increases in the early stages of economic growth and decreases as
(1955) Income Inequality Analysis
economies mature.
Empirical
Barro, R. J. Inequality and Growth Found a positive relationship between inequality and growth in rich
Panel Data
(2000) in a Panel of Countries countries, but a negative relationship in poor countries.
Analysis
Deininger, New Ways of Looking Cross-Country
Showed that high inequality in developing countries hinders
K., & Squire, at Old Issues: Empirical
economic growth by limiting access to resources and opportunities.
L. (1998) Inequality and Growth Analysis
A Reassessment of the Empirical
Forbes, K. J. Found that higher income inequality is associated with faster
Relationship Between Analysis Using
(2000) economic growth, particularly in the short term.
Inequality and Growth Panel Data
Galor, O., &
Income Distribution Theoretical Argued that income inequality negatively impacts economic growth
Zeira, J.
and Macroeconomics Model by restricting investment in human capital.
(1993)
The Price of
Inequality: How
Stiglitz, J. E. Analytical Discussed how high levels of inequality can lead to lower growth
Today's Divided
(2012) Narrative due to reduced aggregate demand and political instability.
Society Endangers Our
Future
This table organizes the major findings of the incentivize investment and innovation, which
literature on income inequality and economic in turn drives economic growth (Barro, 2000).
growth, offering a concise overview of different According to this view, income inequality can
perspectives and empirical results that have
be a sign of a healthy, growing economy where
shaped our understanding of this complex
relationship. individuals are rewarded for their productivity
and risk-taking (Forbes, 2000). However, this
3.1. Theoretical Perspectives on Income perspective has been criticized for overlooking
Inequality and Economic Growth the long-term social and economic costs of
high inequality, such as reduced social
The relationship between income inequality mobility and increased political instability
and economic growth has been the subject of (Wilkinson & Pickett, 2010; Ostry, Berg, &
extensive theoretical debate, with various Tsangarides, 2014).
schools of thought offering different
perspectives. Classical economic theories, In contrast, the endogenous growth theory
such as those proposed by Kuznets (1955), posits that high levels of income inequality can
suggest that income inequality initially rises be detrimental to economic growth,
with economic growth and eventually particularly in the long run. This theory
decreases as economies mature, leading to the suggests that inequality can limit access to
well-known "Kuznets Curve" hypothesis. This education and healthcare, which are crucial
perspective implies that inequality is a for human capital development, thereby
temporary and inevitable phase of stifling economic growth (Galor & Zeira,
development (Kuznets, 1955). However, this 1993). Additionally, the concentration of
theory has been challenged by recent studies, wealth in the hands of a few can lead to
particularly in the context of developing underconsumption and reduced aggregate
economies where the predicted decline in demand, further slowing down economic
inequality has not always materialized growth (Stiglitz, 2012).
(Piketty, 2014; Stiglitz, 2012).
These theoretical perspectives highlight the
Neoclassical economists argue that some complexity of the relationship between
degree of income inequality is necessary to income inequality and economic growth.
While some theories emphasize the potential
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benefits of inequality in fostering growth, these contexts suggests that while the curve
others point to the significant risks it poses to may describe a general trend observed in
sustainable economic development. This historical data from developed countries, it
theoretical dichotomy underscores the need does not fully account for the complexities
for empirical research to provide more present in modern, developing economies.
nuanced insights into this relationship.
Furthermore, studies such as those by Galor
Discussion and Zeira (1993) and Stiglitz (2012) argue that
high levels of income inequality can be
The Kuznets Curve is one of the most detrimental to long-term economic growth,
influential theoretical perspectives in particularly when it limits human capital
understanding the relationship between formation. These researchers contend that in
income inequality and economic growth. the presence of significant inequality, large
Proposed by Simon Kuznets in 1955, the curve segments of the population may lack access to
hypothesizes that as an economy develops, education and other opportunities, leading to
inequality first increases and then decreases, a less skilled workforce and reduced economic
following an inverted-U shape (Kuznets, productivity. This perspective contrasts with
1955). The initial rise in inequality is the Kuznets Curve by suggesting that instead
attributed to the structural changes in the of an inevitable decline in inequality,
economy during the early stages of unchecked inequality can create barriers to
industrialization, where wealth tends to sustainable economic growth. The emphasis
concentrate among those who can capitalize here is on the role of equitable access to
on new economic opportunities. As the resources and opportunities as critical
economy matures and more people gain access components of a growing economy, which the
to education, better jobs, and social mobility, classical Kuznets hypothesis does not fully
inequality is expected to decrease. This theory address.
has been foundational in the study of income
inequality, offering a lens through which the The analysis of development inequality
dynamic interplay between economic growth among districts/cities in East Kalimantan
and income distribution can be understood. Province for the years 2010-2012 examined
Kuznets' inverted U hypothesis using Pearson
correlation analysis to determine the
However, recent empirical studies have relationship between economic growth and
challenged the universality of the Kuznets the Williamson index. The analysis yielded
Curve, particularly in the context of the following results: Based on the Pearson
developing economies. For instance, research correlation analysis between economic
by Deininger and Squire (1998) shows that the growth and the Williamson index, it was
predicted decline in inequality does not always concluded that economic growth has a
negative correlation value of -0.333. This
materialize in developing countries, where
means that there is an inverse relationship
inequality can persist or even worsen as between the two variables; as economic
growth continues. This persistence of growth increases, development inequality
inequality is often linked to factors such as tends to increase as well (Yuliani, 2015).
weak institutions, lack of access to quality
education and healthcare, and entrenched Similarly, Kuznets' curve hypothesis has been
social hierarchies that prevent broad-based validated in West Sumatra Province,
participation in economic growth. The Indonesia. This means that, at the beginning
of the development process, regional
divergence from the Kuznets hypothesis in
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inequality tends to increase. However, as
development progresses and the mobility of 3.2. Empirical Evidence from
capital and labor improves, regional Developed and Developing Economies
inequality begins to decrease. Therefore, once
the country has advanced, regional inequality
is expected to diminish, resembling an Empirical studies on the relationship between
inverted "U" shape (Oktarina, 2023). income inequality and economic growth have
produced mixed results, reflecting the
The results from the graphical analysis show complexity of this relationship across different
that the relationship between Economic economic contexts. In developed economies,
Growth and Income Inequality forms an some studies have found a positive correlation
inverted U-shape. This indicates that in the between income inequality and economic
early stages of economic growth, there is an
growth, suggesting that inequality can
increase in income inequality, as evidenced by
the continuous growth of economic stimulate growth by providing incentives for
performance from 2001 to 2010, which was investment and innovation (Forbes, 2000;
accompanied by rising income inequality. Barro, 2000). However, this positive
Subsequently, from 2011 to 2020, while relationship is often contingent on specific
economic growth continued, income conditions, such as the presence of strong
inequality decreased. This inverted U-shape institutions and social safety nets that can
graph demonstrates that Kuznets' Hypothesis
holds true for West Nusa Tenggara Province mitigate the negative effects of inequality
from 2001 to 2020. This means that an (Aghion, Caroli, & García-Peñalosa, 1999).
increase in economic growth is associated
with a decrease in income inequality (Sirtama, In contrast, research in developing economies
2021). often highlights the negative impact of income
inequality on economic growth. High levels of
In light of these findings, it becomes clear that inequality in these contexts are frequently
the relationship between income inequality associated with reduced access to education
and economic growth cannot be fully and healthcare, which are critical for human
explained by the Kuznets Curve alone. While capital formation and long-term growth
the curve provides a valuable framework for (Banerjee & Duflo, 2003; Deininger & Squire,
understanding how inequality might evolve 1998). For example, a study by Berg, Ostry,
during the early stages of economic and Zettelmeyer (2012) found that income
development, it does not adequately capture inequality significantly hampers economic
the diverse factors that influence this growth in developing countries by creating
relationship in different contexts. The barriers to social mobility and limiting the
variation in outcomes across different potential of lower-income individuals to
economies highlights the importance of contribute to the economy.
considering other factors such as institutional
quality, social policies, and the broader global Furthermore, the impact of income inequality
economic environment when analyzing the on economic growth may also vary depending
interplay between inequality and growth. on the specific measures of inequality used.
Thus, contemporary research suggests that Studies that focus on income distribution
policymakers need to move beyond the among different income groups, rather than
Kuznets Curve and adopt more nuanced general measures of inequality such as the
approaches that address the specific Gini coefficient, often reveal more nuanced
challenges faced by their economies in insights. For instance, research by
fostering inclusive and sustainable growth. Voitchovsky (2005) suggests that while
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inequality at the top end of the income empirical evidence overwhelmingly points to a
distribution may spur growth, inequality at the negative relationship between income
lower end tends to hinder it by reducing access inequality and economic growth. High levels
to opportunities for the poor. of inequality in these contexts often correlate
with limited access to education, healthcare,
These empirical findings suggest that the and economic opportunities for large
relationship between income inequality and segments of the population, thereby stunting
economic growth is highly context dependent. human capital development and economic
While some levels of inequality may indeed productivity (Banerjee & Duflo, 2003).
promote growth under certain conditions, Research by Deininger and Squire (1998)
excessive inequality, particularly in supports this view, showing that in developing
developing economies, is more likely to countries, persistent inequality can act as a
undermine sustainable economic significant barrier to sustainable economic
development. This complexity highlights the growth by entrenching poverty and limiting
importance of tailored policy interventions the potential for widespread economic
that consider the specific economic and social participation. This suggests that the
context of each country. detrimental effects of inequality are more
pronounced in economies where access to
Discussion basic services and opportunities is already
constrained.
Empirical evidence from both developed and
developing economies provides a nuanced Moreover, the persistence of inequality in
understanding of the relationship between developing economies also points to the role of
income inequality and economic growth, weak institutions and governance structures
revealing how this relationship varies in exacerbating the negative impact of
depending on the economic context. In inequality on growth. Studies like those by
developed economies, studies often indicate Acemoglu, Johnson, and Robinson (2001)
that income inequality can have a complex, highlight how weak institutional frameworks
sometimes positive, impact on economic in many developing countries fail to address
growth. For instance, Forbes (2000) found the underlying causes of inequality, such as
that in certain contexts, income inequality corruption, lack of property rights, and
may actually promote economic growth by ineffective legal systems. These factors not
incentivizing individuals to innovate and only perpetuate inequality but also inhibit
invest, particularly in environments where economic growth by creating an environment
strong institutions mitigate the negative where economic resources are not allocated
consequences of inequality. This suggests that efficiently. The lack of effective redistribution
in economies with robust legal and social mechanisms further exacerbates the situation,
frameworks, the potentially harmful effects of making it difficult for these economies to
inequality, such as reduced social mobility and achieve inclusive growth.
political instability, can be counterbalanced by
these institutional strengths, leading to a The contrasting empirical evidence between
scenario where inequality and growth can developed and developing economies
coexist. underscores the importance of context in
understanding the relationship between
However, the situation in developing income inequality and economic growth.
economies is markedly different. Here, the While some degree of inequality may be
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446
compatible with growth in developed corruption and inefficiency, leading to
economies, in developing countries, excessive suboptimal outcomes (Acemoglu & Robinson,
inequality is more likely to hinder growth by 2012).
restricting access to essential resources and
opportunities. This highlights the need for The role of institutions extends beyond
targeted policy interventions that address the taxation and redistribution. Effective
specific challenges faced by developing institutions are also crucial for ensuring that
economies, such as improving institutional economic growth is inclusive and benefits a
quality, expanding access to education and broad spectrum of society. This includes
healthcare, and implementing effective enforcing property rights, reducing
redistribution policies. These measures are corruption, and ensuring that markets are
crucial for ensuring that economic growth is competitive and accessible to all (North,
both inclusive and sustainable, particularly in 1990). Strong institutions can help create an
contexts where inequality poses a significant environment where income inequality does
barrier to development. not become a barrier to growth, but rather a
driver of innovation and productivity.
3.3. Policy Implications and the Role of Moreover, the global nature of economic
Institutions activity today means that national policies
must also consider the impact of global
The mixed empirical evidence on the inequality. International cooperation on
relationship between income inequality and issues such as tax evasion, trade, and financial
economic growth has significant policy regulation is essential for addressing the root
implications. Policymakers must balance the causes of income inequality and ensuring that
potential growth-enhancing effects of economic growth is shared more equitably
inequality with the need to ensure that growth across countries (Piketty, 2014; Stiglitz, 2012).
is inclusive and sustainable. One key policy This highlights the need for coordinated policy
recommendation is to invest in education and efforts at both the national and international
healthcare, which can help mitigate the levels. The chart above illustrates the key policy
negative effects of inequality by enhancing implications and the role of institutions in
human capital and social mobility (Aghion et managing the relationship between income
al., 1999; Stiglitz, 2012). This approach is inequality and economic growth.
particularly important in developing
economies, where inequality often arises from
unequal access to these essential services.