HDI vs. Migrant share of population
Fades after adjusting for income
Across 187 countries, HDI and Migrant share of population rise and fall together at r = +0.53 (on a scale from −1 to +1, where 0 means no link). Comparing only countries with similar income (GDP per person) shrinks it to -0.09, which could easily be chance (q = 0.53, allowing for the many pairs tested, and allowing for countries in the same region being alike). So the first figure mostly shows richer countries differing from poorer ones, not a link between these two things. Caution: correlation moves sharply once outliers are trimmed.
Comparing countries across the middle half of hdi, 0.628 to 0.862 points, migrant share of population is 11.6% of population higher at the top of that range than the bottom. Comparing only countries with similar national income, the gap reverses, to 5.4% of population the other way.
Link before adjusting (r)+0.531p = 5.5e-15 · 187 countries
After adjusting for national income-0.091p = 0.219 · likely range [-0.23, +0.05]
p, allowing for regions0.328standard error 0.085 · 7 regions
Check for luck (q)0.531across 12,497 pairs
How to read these.r runs from −1 (one goes up as the other goes down) to +1 (they rise together), and 0 means no link. Adjusting for national income means comparing countries with the same GDP per person, so differences in wealth can’t explain the link. Income is used in percentage terms, since an extra $1,000 means more to a poor country than to a rich one. p is how likely a link this strong would be if there were really none. Below 0.05 means it is unlikely to be chance. Very small values are written in short form: 1.1e-32 means a decimal point followed by 31 zeros and then 11, so very close to zero. The likely range is where the true figure probably lies, and a range that crosses zero means the link could easily be chance. Countries in the same region tend to resemble each other, so the third figure allows for that, which gives a fairer p. The standard error is the typical size of the error in r. Finally, testing this many pairs means some will look strong by luck alone. A q below 0.05 means this link is unlikely to be one of those.
HDI · index, 0 to 1link with income +0.96 · proxy
Migrant share of population · % of populationlink with income +0.73 · high
Both of these rise and fall closely with national income, so a strong link between them before adjusting was close to certain. Read the adjusted figure, not the first one.
“Link with income” is how closely each measure tracks GDP per person across countries, from −1 to +1.
Every country as a dot
best-fit line line after adjusting
Four ways to measure the link
| Method | r | p | Countries |
|---|---|---|---|
| Standard (Pearson), not adjusted | +0.531 | 5.5e-15 | 187 |
| By rank (Spearman), not adjusted | +0.698 | 1.3e-28 | 187 |
| Standard (Pearson), adjusted for national income | -0.091 | 0.219 | 187 |
| By rank (Spearman), adjusted for national income | +0.063 | 0.396 | 187 |
The rank version uses only each country’s place in line, from lowest to highest, so a few extreme countries count for less. The adjusted and unadjusted versions use the same 187 countries: those that report both measures and GDP per person. So the gap between them comes from the adjustment, not from a change in which countries are counted. Drop in the size of r after adjusting: +0.440 (a minus sign means it grew).
How solid is it?
Leaving out one country at a time, r ranges from -0.127 (without GUY) to -0.034 (without QAT). The bar above shows that range on a scale from −1 to +1, with the solid line at the full result. The single country that moves r most: QAT (+0.056).
Fragile: this link may not hold up.
- correlation moves sharply once outliers are trimmed
- sign flips once outliers are trimmed
- direction is not consistent across regions
Within each region
Countries are not separate, unrelated cases, and neighbors share a lot. A link that holds inside each region is far more believable than one that shows up only when comparing regions.
| n | r | ||
|---|---|---|---|
| East Asia & Pacific | 30 | +0.07 | |
| Europe & Central Asia | 50 | -0.07 | |
| Latin America & Caribbean | 31 | +0.23 | |
| Middle East, North Africa, Afghanistan & Pakistan | 22 | -0.11 | |
| Sub-Saharan Africa | 46 | -0.02 |
By income third
If the link shows up only in the richest third of countries, it is a feature of rich countries, not a general pattern.
| n | r | ||
|---|---|---|---|
| Poorest third | 63 | -0.12 | |
| Middle third | 62 | +0.15 | |
| Richest third | 62 | -0.09 |
By largest religious group
Countries grouped by a label they share, such as main religion, rather than by a number. Groups of fewer than twelve countries are not shown. These groups differ in income, region and history all at once. So a gap between them is a place to start asking questions, not an answer.
| n | r | ||
|---|---|---|---|
| Christians | 108 | +0.07 | |
| Muslims | 49 | -0.11 |
By last european coloniser
Countries grouped by a label they share, such as main religion, rather than by a number. Groups of fewer than twelve countries are not shown. These groups differ in income, region and history all at once. So a gap between them is a place to start asking questions, not an answer.
| n | r | ||
|---|---|---|---|
| France | 25 | -0.03 | |
| Never a European colony | 21 | -0.16 | |
| Spain | 20 | -0.16 | |
| United Kingdom | 63 | +0.08 |
Without outliers (countries far outside the middle half of countries on either measure, by more than one and a half times the width of that middle half): r = +0.059 after dropping 13 countries.
Two series, one country
Both measures over the years for one country you pick. The two charts are stacked so they share only the years along the bottom.
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Over time, within countries
Everything above compares countries with each other at one moment. This section compares each country only with itself over 31years. So a link here can’t come from anything about a country that stays the same, such as its history, geography, institutions or culture.
Within countries over time, there is no link that is clearly more than chance (r = -0.090, comparing each country only with itself over the years, and each year only with the same year elsewhere). Whatever the cross-country picture shows, countries whose hdi moved did not tend to see their migrant share of population move with it.
Across countries (adjusted)-0.091for comparison
Within countries+0.179each country vs itself
…and vs the same year elsewhere-0.090q = 0.189 · 171 countries
Year-on-year changes—q = —
The direction flips. Comparing each country only with itself gives +0.18. Also taking out what happened to the whole world each year gives -0.09. So the first figure was picking up a trend both measures share with worldwide progress, not a link between them.
Read with care.
- Almost all of this indicator's variation is between countries, not within them, so the within-country estimate rests on a small part of the data.
1,145 country-years (one country in one year), 171 countries, 1990–2020, about 7 years each on average. Share of the variation that happens within countries over time: 10% for HDI, 4% for Migrant share of population. The margins of error allow for each country appearing many times, and for each year’s value being close to the year before.
Year-to-year changes are a cautious test, not a final answer. Looking only at changes from one year to the next removes each country’s own trends. But it also makes measurement mistakes louder, which pulls the results toward zero. A near-zero result here is weak evidence of no link, not proof.
With one measure years behind the other
Same year (lag 0): -0.090. A peak away from zero does not show which comes first. These series change slowly — this year’s value is close to last year’s. That makes the curve smooth and nearly symmetric, whatever produced the data. Even a sharp peak at one lag (a gap of some years) would not prove that one measure changes the other.
The largest value on this curve (-0.19 at lag -4) is higher than the same-year one by 0.10. That gap is not a finding. It is the largest of 21 closely related estimates, and picking the biggest of many tests always makes it look bigger. That is exactly why nothing on this site is ranked or chosen by lag.
The data
index, 0 to 1 | % of population | Years | |
|---|---|---|---|
| Iceland ISL | 0.972 | 25.1% | 2023, 2024 |
| Norway NOR | 0.97 | 18.2% | 2023, 2024 |
| Switzerland CHE | 0.97 | 31.1% | 2023, 2024 |
| Denmark DNK | 0.962 | 14.2% | 2023, 2024 |
| Sweden SWE | 0.959 | 21.4% | 2023, 2024 |
| Germany DEU | 0.959 | 19.8% | 2023, 2024 |
| Australia AUS | 0.958 | 30.4% | 2023, 2024 |
| Netherlands NLD | 0.955 | 16.2% | 2023, 2024 |
| Hong Kong SAR, China HKG | 0.955 | 41.3% | 2023, 2024 |
| Belgium BEL | 0.951 | 20% | 2023, 2024 |
| Ireland IRL | 0.949 | 23.1% | 2023, 2024 |
| Finland FIN | 0.948 | 9.2% | 2023, 2024 |
| Singapore SGP | 0.946 | 48.7% | 2023, 2024 |
| United Kingdom GBR | 0.946 | 17.1% | 2023, 2024 |
| United Arab Emirates ARE | 0.94 | 74% | 2023, 2024 |
United Nations Development Programme, Human Development Report 2025
World Bank, World Development Indicators
Sources
HDI
Human Development Index
United Nations Development Programme, Human Development Report Office · via Our World in Data · CC BY 3.0 IGO · updated annual
The geometric mean (a kind of average that multiplies the parts together) of three parts: income per person (GNI per capita), life expectancy, and schooling (expected years and average years). All four inputs are on this site, and each is flagged. So a link between the HDI and any of them is shown for what it is: the index matching a part of itself. For the same reason it is kept out of this site's own topic scores. Those already contain its parts, and adding it would count each twice. It is the most-cited development index there is. It is here mostly so its parts can be read separately.
Migrant share of population
International migrant stock (% of population)
UN Population Division, International Migrant Stock · CC BY 4.0 · updated quarterly
People living outside the country they were born in, as a share of the population. It counts people at one moment, while the net migration already on the site counts moves over a year. Published every five years until 2020, and for 2024.
How this was computed
Data used: most recent value in 2010-2025; values come from 2023–2024. To adjust for income, each measure is first predicted from GDP per person (in percentage terms, on a log scale) with a straight-line fit. Only what is left over is then compared. This is called a partial correlation. The line is drawn the standard way (ordinary least squares), which picks the line that comes closest to all the countries at once. The error margins allow for countries in the same region resembling each other, using 7 World Bank regions. The q-value corrects for testing all 12,497 pairs at once, using the Benjamini–Hochberg method. Underlying data last updated DYB 2024. How the country data works · explore HDI and Migrant share of population
This page shows that two measures go together. It does not show that HDI changes Migrant share of population, or the reverse. These figures also describe countries, not individual people. See the ecological fallacy.
More links with HDI or Migrant share of population
- HDI vs Under-5 mortality before -0.85 → after adjusting -0.56
- HDI vs Tertiary enrollment before +0.81 → after adjusting +0.52
- HDI vs Maternal mortality before -0.77 → after adjusting -0.47
- Anaemia in women vs HDI before -0.73 → after adjusting -0.47
- HDI vs Married by 18 before -0.70 → after adjusting -0.47
- HDI vs PISA science before +0.82 → after adjusting +0.46
- HDI vs Population 65+ before +0.79 → after adjusting +0.44
- HDI vs Skilled birth attendance before +0.75 → after adjusting +0.43