There is strong correlation of top countries in the list with the list of happiest countries in the world.

https://worldpopulationreview.com/country-rankings/happiest-...

Top 10 in the paper (from appendix):

Iceland, Switzerland, Norway, Sweden, Finland, Denmark, Netherlands, Canada, Estonia, Luxembourg

Top 10 happiest countries:

Finland, Denmark, Switzerland, Iceland, Norway, Netherlands, Sweden, New Zealand, Austria, Luxembourg