23.01.28 · economics / development

Development economics

draft3 tiersLean: none

Anchor (Master): Mas-Colell, Whinston & Green, Microeconomic Theory; relevant academic sources

Intuition [Beginner]

GDP measures the size of an economy, but it does not capture whether people can read, whether children survive to adulthood, whether clean water comes out of a tap, or whether citizens have a voice in how they are governed. Economic development is broader than economic growth: it encompasses improvements in health, education, living standards, and institutional quality -- the things that make life not just richer but better.

Consider two countries with the same GDP per capita. Country A has high infant mortality, low literacy, a repressive government, and an economy based on exporting a single natural resource. Country B has low infant mortality, high literacy, democratic institutions, and a diversified economy. Both have the same income, but Country B is more developed.

The central questions of development economics are: why are some countries rich and others poor? What can poor countries do to develop? And what role, if any, should rich countries, international institutions, and foreign aid play?

These questions have no simple answers. Geography, institutions, history, culture, and global economic structures all matter. Different schools of thought emphasise different factors and propose different policy prescriptions, and the empirical evidence is often contested.

Visual [Beginner]

GDP per capita vs Human Development

  High  |          . Sweden, Norway
  HDI   |        .  Japan, Canada
        |      .
        |    .   .  Mexico, Brazil
        |   .          . China, Turkey
        |  .                .
        | .   .                  .
  Low   |.         .                   . Nigeria
  HDI   |                . Bangladesh        . DR Congo
        +------------------------------------------
        Low                           High
                 GDP per capita

  Some countries punch above their GDP (Cuba: high HDI, low GDP).
  Others punch below (oil-rich states: high GDP, lower HDI).


Development Indicators

  GDP per capita     ---- Income
  Life expectancy    ---- Health
  Literacy rate      ---- Education
  HDI                ---- Composite (income + health + education)
  Gini coefficient  ---- Inequality
  Poverty rate       ---- Absolute deprivation

Worked Example [Beginner]

The Human Development Index (HDI) combines three dimensions into a single score from 0 to 1:

Health: Life expectancy at birth
Education: Mean years of schooling + expected years of schooling
Income: GNI per capita (PPP-adjusted)

Each dimension is normalised to a 0-1 scale. The HDI is the geometric mean of the three dimension indices:

$H D I = (I_{h e a l t h} \times I_{e d u c a t i o n} \times I_{in co m e})^{1/3}$

Consider Country X:

Life expectancy: 75 years (index = 0.85)
Education index: 0.70
GNI per capita: $15,000 (index = 0.75)

$H D I = (0.85 \times 0.70 \times 0.75)^{1/3} = (0.44625)^{1/3} \approx 0.765$

This places Country X in the "high human development" category (0.7-0.8). Compare with Norway (HDI ~ 0.96), India (HDI ~ 0.64), and Niger (HDI ~ 0.39).

The geometric mean ensures that a country cannot compensate for a very low score in one dimension with a high score in another. A country with excellent income but terrible health outcomes will have a lower HDI than a country that is moderate in all three.

Check Your Understanding [Beginner]

Formal Definition [Intermediate+]

Measuring development

The Human Development Index is computed as:

$H D I = (I_{h e a l t h} \cdot I_{e d u c a t i o n} \cdot I_{in co m e})^{1/3}$

where each dimension index is computed as:

$I_{j} = \frac{x _{j} - x _{j, min}}{x _{j, ma x} - x _{j, min}}$

For the income dimension, the transformation uses the logarithm:

$I_{in co m e} = \frac{ln ( GN I _{p c} ) - ln ( 100 )}{ln ( 75 , 000 ) - ln ( 100 )}$

reflecting the diminishing returns of income to well-being.

Poverty measurement

The Foster-Greer-Thorbecke (FGT) class of poverty measures:

$P_{α} = \frac{1}{n} i = 1 \sum n (\frac{z - y _{i}}{z})^{α} \cdot 1_{y_{i} < z}$

where $z$ is the poverty line, $y_{i}$ is individual income, and $α$ is a parameter:

$α = 0$ : Headcount ratio (fraction below the poverty line)
$α = 1$ : Poverty gap (average depth of poverty below the line)
$α = 2$ : Squared poverty gap (emphasises the poorest of the poor)

Growth models and development

The Solow growth model predicts conditional convergence: poorer countries grow faster than richer ones, conditional on having similar savings rates, population growth, and technology. The failure of unconditional convergence (poor countries do not systematically grow faster than rich ones) suggests that the conditions differ systematically -- which is precisely what development economics tries to understand.

Institutional analysis

Acemoglu, Johnson, and Robinson (2001) demonstrated that institutions (specifically, the security of property rights) are a significant determinant of income levels, even after instrumenting for endogeneity using colonial mortality rates. Their framework distinguishes:

Inclusive institutions: Secure property rights, rule of law, competitive markets, broad access to economic opportunities.
Extractive institutions: Concentrated power, insecure property rights, barriers to entry, rent-seeking by elites.

Key Concepts [Intermediate+]

Economic development: Improvements in living standards, health, education, and institutional quality, beyond income growth alone.
Economic growth: An increase in real GDP or GDP per capita. Necessary but not sufficient for development.
Human Development Index (HDI): A composite measure combining health (life expectancy), education, and income. Published annually by the UN.
Absolute poverty: Deprivation measured against a fixed standard (e.g., the World Bank's $2.15/day line).
Resource curse: The paradox that countries with abundant natural resources often experience slower growth, more corruption, and worse development outcomes than resource-poor countries.
Dutch disease: The phenomenon whereby resource exports appreciate the exchange rate, making other tradable goods uncompetitive.
Institutions: The formal and informal rules governing economic and political life. Increasingly regarded as the fundamental determinant of development outcomes.
Foreign aid: Transfers from rich countries or international institutions to developing countries. Controversial: some evidence of effectiveness, some evidence of dependency and distortion.
Structural adjustment: Policy conditions imposed by the IMF and World Bank on borrowing countries, typically including fiscal austerity, trade liberalisation, and privatisation. Controversial in both design and outcomes.
Industrial policy: Government interventions to promote specific industries or sectors. Widely used by successful developers (South Korea, Taiwan, China) despite neoclassical scepticism.

Exercise 1. Country X has a headcount poverty ratio of 30% and a poverty gap index of 10% (with $α = 1$ ). Interpret both numbers. What additional information does the squared poverty gap ( $α = 2$ ) provide?

Exercise 2. Explain why conditional convergence (in the Solow model) does not imply that poor countries will catch up to rich countries in practice. What additional factors might prevent convergence?

Academic Perspectives [Master]

Neoclassical / mainstream view

The neoclassical approach to development emphasises market liberalisation, trade openness, and institutional reform. The "Washington Consensus" (Williamson, 1990) summarised this view: fiscal discipline, trade liberalisation, privatisation, deregulation, and secure property rights. The expectation was that integrating poor countries into the global market would promote convergence.

Results have been mixed. Some countries that adopted Washington Consensus policies grew rapidly (Chile, Poland). Others experienced stagnant growth, increased poverty, and financial crises (many sub-Saharan African and Latin American countries in the 1980s-1990s). The East Asian "tiger" economies (South Korea, Taiwan, Singapore) developed through heavy state intervention, industrial policy, and trade protection -- contradicting the free-trade prescription.

Modern neoclassical development economics, led by economists like Esther Duflo, Abhijit Banerjee, and Michael Kremer (Nobel Prize, 2019), uses randomised controlled trials (RCTs) to evaluate specific interventions: deworming programmes, microfinance, conditional cash transfers, educational subsidies. This approach, sometimes called the "randomista" movement, focuses on identifying what works at the micro level rather than prescribing grand theories of development.

Critics argue that RCTs, while useful, cannot address the structural and macroeconomic determinants of development. Knowing that deworming improves school attendance does not explain why some countries are poor and others rich.

Institutional school

The institutional approach, following North (1990) and Acemoglu and Robinson (2012), argues that institutions are the fundamental cause of development differences. Countries with inclusive institutions develop; those with extractive institutions do not. Policy interventions that ignore institutional context (e.g., structural adjustment in countries with weak institutions) will fail.

Acemoglu, Johnson, and Robinson (2001) used settler mortality in former colonies as an instrument for institutional quality, finding a large causal effect of institutions on income. The argument: where European settlers faced high mortality (tropical colonies), they established extractive institutions designed to transfer wealth to the coloniser. Where settlers could survive (North America, Australia), they established inclusive institutions that persisted after independence.

Critics question the instrument (settler mortality data may be unreliable), the monocausal emphasis on institutions, and the difficulty of operationalising the framework for policy (how do you change institutions?).

Structuralist / dependency school

Structuralist development economics, associated with Prebisch (1950) and Singer (1950), argued that the global economic structure disadvantages developing countries. The Prebisch-Singer hypothesis holds that the terms of trade for commodity-exporting countries decline over time relative to manufactured goods, trapping them in a cycle of poverty. The policy implication is import substitution industrialisation (ISI): protecting domestic industries with tariffs and subsidies to build manufacturing capacity.

Dependency theory (Frank, 1966; Wallerstein, 1974) went further, arguing that the global capitalist system structures the relationship between core (rich) and periphery (poor) countries in ways that systematically transfer wealth from periphery to core. Development and underdevelopment are not separate processes but two sides of the same coin: the core develops by extracting resources and surplus from the periphery.

ISI produced mixed results: significant industrialisation in Brazil and Mexico, but eventually leading to inefficiency, debt, and inflation. The East Asian success with export-oriented growth undermined the case for protection, though the East Asian states also used extensive industrial policy.

Marxian perspective

Marxian development theory views underdevelopment as a consequence of capitalist imperialism. The extraction of surplus from colonies and post-colonial peripheries -- through unequal trade, debt servitude, land grabs, and control of natural resources -- perpetuates underdevelopment. Development in the core requires underdevelopment in the periphery.

Modern Marxian analysis focuses on the role of multinational corporations, structural adjustment conditionalities, and intellectual property regimes in maintaining core-periphery inequalities. The policy prescription is not reform within the global capitalist system but restructuring the system itself -- through nationalisation, South-South cooperation, and resistance to imperialist economic structures.

Critics note that this analysis does not adequately explain the successful development of some former peripheral countries (South Korea, Taiwan, China) within the global capitalist system, nor does it account for the failure of some socialist development strategies.

Heterodox approaches

Capability approach (Sen, 1999): Amartya Sen redefined development as the expansion of human capabilities -- what people are able to do and be. Poverty is not merely low income but the deprivation of capabilities (health, education, political participation). This philosophical framework underlies the HDI and shifts the focus from income to freedom.

Complexity economics (Hausmann and Hidalgo, 2009): The "economic complexity" index measures the diversity and sophistication of a country's productive capabilities. Countries with more complex economies grow faster. Development is a process of accumulating productive capabilities, not simply accumulating capital.

Historical Context [Master]

Post-war development economics (1940s-1960s): The field emerged as former colonies gained independence. Early theories (Rostow's stages of growth, Harrod-Domar model) focused on capital accumulation and industrialisation as the path to development. The dominant approach assumed that poor countries lacked capital and that investment (funded by foreign aid or domestic savings) would trigger take-off.
Import substitution (1950s-1970s): Many Latin American and African countries adopted ISI, protecting domestic industries to reduce dependence on imports. Initial success gave way to inefficiency, debt, and inflation.
East Asian miracle (1960s-1990s): South Korea, Taiwan, Singapore, and Hong Kong developed rapidly through export-oriented growth, extensive industrial policy, investment in education, and (in some cases) land reform. The World Bank's 1993 report attributed their success to "market-friendly" policies, but critics noted the heavy role of state direction.
Debt crisis and structural adjustment (1980s-1990s): The Latin American debt crisis (1982) and sub-Saharan African debt crises led to IMF and World Bank structural adjustment programmes. Countries were required to cut spending, liberalise trade, and privatise state enterprises in exchange for loans. Results were deeply contested: some stabilisation occurred, but social spending was often cut, poverty increased, and growth remained sluggish.
Millennium Development Goals (2000-2015): The UN established eight development goals (halve extreme poverty, achieve universal primary education, reduce child mortality, etc.). The goals were largely achieved at the global level, driven primarily by Chinese growth.
Sustainable Development Goals (2015-2030): A broader set of 17 goals encompassing poverty, inequality, climate, and governance. The ambition is greater, but progress has been uneven.
China's rise (1978-present): China's development trajectory -- from one of the world's poorest countries to the second-largest economy -- is the most consequential development event of the past half-century. It combined state direction, market liberalisation, export-oriented manufacturing, and massive investment in infrastructure and education, but also produced severe environmental damage, inequality, and political repression.

Bibliography [Master]

Acemoglu, D., Johnson, S., & Robinson, J. A. (2001). The colonial origins of comparative development: An empirical investigation. American Economic Review, 91(5), 1369-1401.
Acemoglu, D., & Robinson, J. A. (2012). Why Nations Fail: The Origins of Power, Prosperity, and Poverty. Crown Business.
Banerjee, A. V., & Duflo, E. (2011). Poor Economics: A Radical Rethinking of the Way to Fight Global Poverty. PublicAffairs.
Easterly, W. (2006). The White Man's Burden: Why the West's Efforts to Aid the Rest Have Done So Much Ill and So Little Good. Penguin.
Hausmann, R., & Hidalgo, C. A. (2009). The building blocks of economic complexity. Proceedings of the National Academy of Sciences, 106(26), 10570-10575.
North, D. C. (1990). Institutions, Institutional Change and Economic Performance. Cambridge University Press.
Prebisch, R. (1950). The Economic Development of Latin America and Its Principal Problems. United Nations.
Sen, A. (1999). Development as Freedom. Oxford University Press.