Do Electoral democracy and Marriage rate go together across countries?

Across 46 countries the link before adjusting for anything is r = -0.55, on a scale from -1 (opposite) to +1 (in step). A version that uses only each country's rank gives -0.23.

Does the link hold within countries over time, not just across countries?

Comparing each country only with itself across 1990-2022, and setting aside what happened worldwide in each year, the link is -0.117 (44 countries, 1,366 country-years). Using year-to-year changes, it is -0.069.

Does Electoral democracy cause Marriage rate?

This analysis cannot answer that. It shows only that the two go together. A link between two country measures, adjusted or not, does not show that either one changes the other. Country figures also say nothing about individual people.

Electoral democracy vs. Marriage rate

Fades after adjusting for income

Across 46 countries, Electoral democracy and Marriage rate rise and fall together at r = -0.55 (on a scale from −1 to +1, where 0 means no link). Comparing only countries with similar income (GDP per person) leaves r = -0.61, which could easily be chance (q = 0.090, allowing for the many pairs tested, and allowing for countries in the same region being alike). Caution: leave-one-out range spans 0.17 in r.

Comparing countries across the middle half of marriage rate, 3.7 to 5.33 marriages per 1,000 people, electoral democracy is worse by 0.0995 points at the top of that range than the bottom. Comparing only countries with similar national income, the gap is 0.0943 points.

Link before adjusting (r)-0.551p = 7.2e-5 · 46 countries

After adjusting for national income-0.609p = 9.0e-6 · likely range [-0.77, -0.38]

p, allowing for regions0.015standard error 0.148 · 5 regions

Check for luck (q)0.090across 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.

Electoral democracy · index (0-1)link with income +0.49 · moderate

Marriage rate · marriages per 1,000 peoplelink with income -0.06 · independent

“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	-0.551	7.2e-5	46
By rank (Spearman), not adjusted	-0.232	0.121	46
Standard (Pearson), adjusted for national income	-0.609	9.0e-6	46
By rank (Spearman), adjusted for national income	-0.250	0.098	46

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 46 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: -0.058 (a minus sign means it grew).

How solid is it?

Leaving out one country at a time, r ranges from -0.664 (without CYP) to -0.498 (without CHN). 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: CHN (+0.112).

Fragile: this link may not hold up.

leave-one-out range spans 0.17 in r
correlation moves sharply once outliers are trimmed

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
Europe & Central Asia	32	-0.43

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	16	-0.81
Middle third	15	-0.05
Richest third	15	-0.38

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	38	-0.45

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 = -0.080 after dropping 6 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 33years. 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 = -0.117, 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 electoral democracy moved did not tend to see their marriage rate move with it.

Across countries (adjusted)-0.609for comparison

Within countries-0.167each country vs itself

…and vs the same year elsewhere-0.117q = 0.494 · 44 countries

Year-on-year changes-0.069q = 0.214

1,366 country-years (one country in one year), 44 countries, 1990–2022, about 31 years each on average. Share of the variation that happens within countries over time: 41% for Electoral democracy, 29% for Marriage rate. 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): -0.117. 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 data

	index (0-1)	marriages per 1,000 people	Years
Denmark DNK	0.913	5.34	2025, 2022
Norway NOR	0.89	3.8	2025, 2022
Sweden SWE	0.889	4.6	2025, 2022
Belgium BEL	0.889	4.2	2025, 2022
Ireland IRL	0.887	3.3	2025, 2021
Estonia EST	0.887	5.3	2025, 2022
Switzerland CHE	0.882	4.7	2025, 2022
Luxembourg LUX	0.869	3.8	2025, 2022
France FRA	0.865	3.6	2025, 2022
Costa Rica CRI	0.862	4.39	2025, 2022
Finland FIN	0.852	3.9	2025, 2022
New Zealand NZL	0.849	3.68	2025, 2022
Czechia CZE	0.849	5.1	2025, 2022
Australia AUS	0.844	4.89	2025, 2022
Canada CAN	0.84	2.6	2025, 2020

Coppedge, M. et al., V-Dem Dataset, Varieties of Democracy (V-Dem) Project
OECD Family Database, indicators SF3.1 (marriage and divorce rates) and SF1.2 (children in families); US series before 1990 from the US Census Bureau and CDC/NCHS

Sources

Electoral democracy

Electoral democracy index (polyarchy)

V-Dem Institute, University of Gothenburg · via Our World in Data · CC BY 4.0 · updated annual

Based on political scientist Robert Dahl's idea of "polyarchy": are leaders chosen in free and fair elections, with freedom of speech, freedom to form groups, and the vote for nearly all adults? It is the base index that most other V-Dem measures are built on.

Marriage rate

Crude marriage rate

OECD · via Our World in Data · CC BY 4.0 (OECD terms and conditions) · updated annual

Registered marriages in the year per 1,000 people (counted at mid-year), from official records. Couples living together and registered partnerships are left out. So the rate shows how often people marry, and nothing about how many live as couples. New Zealand counts civil unions. Same-sex marriages count in each country's figure from the year it made them legal. This is the only ready-made series that compares countries. It covers only OECD members, about forty countries, nearly all of them rich. So its links with other measures are worked out over only a third of the countries on the site, and adjusting for GDP has less to remove. The low points in 2020 are the pandemic, not a break in the series. But the British and Canadian series stop at 2020, so their latest value is that low point: 1.4 and 2.6, against 3.7 and 3.9 the year before. The links with the governance measures stay the same using pre-pandemic values, or with both countries removed. No "better" direction is set: it describes how people live, not how well a country is doing.

How this was computed

Data used: most recent value in 2010-2025; values come from 2012–2025. 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 5 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 Electoral democracy and Marriage rate

This page shows that two measures go together. It does not show that Electoral democracy changes Marriage rate, or the reverse. These figures also describe countries, not individual people. See the ecological fallacy.