06 — Research Hub
The library behind the lab
Every number in this project traces back to a source. Here are the papers, books, datasets, and definitions that shaped the research.
Sources & Further Reading
Research papers, books, and reports
Where is the Land of Opportunity? The Geography of Intergenerational Mobility in the United States
Raj Chetty et al. · 2014
The Economics of Inequality
Thomas Piketty · 2014
Capital in the Twenty-First Century
Thomas Piketty · 2014
A Broken Social Elevator? How to Promote Social Mobility
OECD · 2018
World Inequality Report
Lucas Chancel et al. · 2022
Human Development Report
UNDP · 2023/24
World Development Indicators
World Bank · 2024
Our World in Data — Income Inequality
Max Roser et al. · 2024
World Inequality Database (WID.world)
WID.world · 2024
The Great Gatsby Curve
Alan Krueger · 2012
Giving Kids a Fair Chance
James Heckman · 2013
The Price of Inequality
Joseph Stiglitz · 2012
Index of Economic Freedom
Heritage Foundation · 2024
OECD Income Distribution Database
OECD · 2024
Global Social Mobility Index
World Economic Forum · 2020
Norton & Ariely on Wealth Inequality Perceptions
Michael Norton & Dan Ariely · 2011
Data Sources
Where the numbers come from
All statistics in this project are drawn from these public, reputable datasets. Nothing is fabricated.
World Bank — World Development Indicators
Gini, poverty, median income, urban population
UNDP — Human Development Reports
HDI, education & health sub-indices
OECD — Income Distribution & Social Mobility
Social mobility, employment, tax revenue
World Inequality Database
Income shares (top 10%, bottom 50%)
Our World in Data
Cross-country inequality & education trends
Heritage Foundation — Index of Economic Freedom
Economic freedom scores
World Economic Forum — Social Mobility Index
Social mobility composite
Opportunity Insights (Chetty Lab)
Intergenerational mobility research
Glossary
Key terms, in plain language
Economics has a jargon problem. These definitions keep the project accessible.
Gini Index
A summary measure of income inequality from 0 (perfect equality) to 100 (one person earns everything).
Social Mobility
The ability of individuals or families to move up or down the income distribution relative to their parents.
Intergenerational Elasticity
A statistic capturing how strongly a parent’s income predicts their child’s. Higher means less mobile — the "Great Gatsby Curve".
Human Development Index (HDI)
A UNDP composite of life expectancy, education, and per-capita income, scored 0 to 1.
Lorenz Curve
A graph plotting cumulative share of income against cumulative share of population. The further it bows from the diagonal, the more unequal the distribution.
Equality of Opportunity
The principle that outcomes should depend on effort and talent, not on circumstances of birth.
Human Capital
The stock of knowledge, skills, and health that people accumulate, which drives their earning potential.
Progressive Taxation
A tax system where the average rate rises with income, redistributing from higher to lower earners.
Poverty Rate
The share of the population living below a defined income threshold, often $6.85 per day PPP for lower-middle-income countries.
Income Share
The percentage of total national income earned by a given group (e.g. the top 10% or bottom 50%).
Economic Freedom
An index measuring property rights, government integrity, and regulatory efficiency.
Tertiary Education
Post-secondary education — universities, colleges, and technical institutes — as a share of adults 25+.
Methodology
How this project was built
The country dataset was compiled from seven public sources — World Bank, UNDP, OECD, World Inequality Database, Our World in Data, Heritage Foundation, and the World Economic Forum Social Mobility Index. Where a country lacked a recent estimate, the most recent available figure was used and noted as approximate.
All values are rounded for display. The Gini index uses the World Bank's most recent estimate per country. HDI and its sub-indices come from the UNDP Human Development Report. Income shares (top 10%, bottom 50%) are drawn from the World Inequality Database.
The Policy Simulation Lab uses a simplified linear model: each slider contributes a weighted delta to four outcome indicators, normalised to a 0–100 scale. The weights are informed by the direction and magnitude of effects reported in OECD and Chetty et al. research, but the model is deliberately transparent and educational — not econometric.
No data was fabricated. Where approximations were necessary for educational clarity, they are flagged in the source notes. The full source list and links are provided above.