Dani Rodrik recently posted a picture from Larry Bartels’ latest book â€“ in which Bartels shows that in the US, inequality rises under Republicans, and falls under Democrats. Here’s the key graph:
What’s curious about this is that it seems to be a finding restricted to the US federal system. In this paper, I look at US states, and find that while the effects are statistically significant, the magnitudes are very small. And using top incomes data, I find no systematic pattern across countries. Here are the top income results, from a chapter that I have forthcoming in the OUP Handbook of Economic Inequality. Basic result â€“ on average, top incomes inequality rises a smidgin faster under right-wing governments (though in Australia, the pattern goes the other way). But in no case is the difference discernable from statistical noise.
Note: Top income shares from Leigh (2007) and partisan coding from Armingeon (2006). The party coding refers to whether right-wing or left-wing parties hold the largest share of cabinet posts. For simplicity, I include centre parties with left-wing parties. The mean difference refers to the mean of the column (i.e. the mean difference for countries that have data on changes in top income shares under both right-wing and left-wing parties). The p-value is from a t-test of equality between right-wing and left-wing governments, with each run of right-wing or left-wing governments treated as a separate observation (e.g. in the United Kingdom case, the period of Conservative rule from 1979-1997 would be treated as a single observation for the purpose of this t-test). For the Netherlands, there is only one run of right-wing governments during this period, so the p-value cannot be estimated. In the last row, the p-value is from a t-test that combines data from all countries.
Update, 8 Apr: On Rodrik’s blog, Bartels responds to some of his critics.