Tables 1 Descriptions of key measures

Value Variation

Item

We normalize responses to the 40 social value items that have been included in each WVS timepoint to a 0–1 scale. We then compute the standard deviation for the global distribution of country means at each timepoint. Higher standard deviations represent more value variation. We can calculate this trend for a single item, or across all items.

A rise in item-level value variation over time indicates value divergence, whereas a decline indicates convergence.

Value Distinctiveness

Country

After normalizing item responses and calculating country means for each item, we take the median value of these country means. This represents the global average of a given item at a particular point in time. We then take the absolute difference between each country mean and the global average. Higher values of this absolute difference mean that a country’s values are dissimilar than most other countries.

Countries with high value distinctiveness across all values are dissimilar from countries in the rest of the world. If value distinctiveness increases in a country over time, this suggests that values in that country are diverging from those of other countries. If value distinctiveness is rising across all countries, this indicates that countries are becoming more dissimilar from each other over time, indicating global value divergence.

Within-Country Heterogeneity

Country

We calculated within-country heterogeneity by applying the same procedure for estimating between-nation value variation to estimate variation of values across people living in the same nation.

Within-country heterogeneity measures whether individuals within countries hold different values. For example, high within-country heterogeneity in the United States might arise because liberal and conservative Americans hold very different values.