There weren’t many jaws on the floor when the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel went to Daron Acemoglu and Simon Johnson of MIT and James Robinson of the University of Chicago. Acemoglu is so prolific he has a blog dedicated to him, featuring “facts” such as “the law of large numbers has been renamed the law of Daron’s citation counts”.

The trio won for research asking why some countries are richer than others, and arguing that institutions, which include things like well-enforced property rights and an independent judiciary, were key for development. More controversially, they claimed to show that events centuries ago are still affecting economic outcomes today.

The idea that institutions matter for growth seems pretty obvious. But how much they matter is less clear. What if factors such as geography influence both institutions and growth, or what if growth itself promotes good institutions? Precision is made harder by institutions being hard to quantify, dreadful historical data and there being only so many countries to batter with statistical tests.