"[...] our measure of competence relies on a comparison of the private incomes across people with the same education, occupation, age, and residence in the same geographical region (members of municipal councils in Sweden typically keep their private job).
A competent politician, we argue, is a person who makes more than the median amongst politicians with similar characteristics."
If that is true, then the person who conducted this study must have a below average income.
I thought the politicians with above average incomes were the corrupt ones.