Estimating the Impact of Gubernatorial Partisanship on Policy Settings and Economic Outcomes: A Regression Discontinuity Approach

Using panel data from US states over the period 1941-2002, I measure the impact of gubernatorial partisanship on a wide range of different policy settings and economic outcomes. Across 32 measures, there are surprisingly few differences in policy settings, social outcomes and economic outcomes under Democrat and Republican Governors. In terms of policies, Democratic Governors tend to prefer slightly higher minimum wages. Under Republican Governors, incarceration rates are higher, while welfare caseloads are higher under Democratic Governors. In terms of social and economic outcomes, Democratic Governors tend to preside over higher median post-tax income, lower post-tax inequality, and lower unemployment rates. However, for 26 of the 32 dependent variables, gubernatorial partisanship does not have a statistically significant impact on policy outcomes and social welfare. I find no evidence of gubernatorial partisan differences in tax rates, welfare generosity, the number of government employees or their salaries, state revenue, incarceration rates, execution rates, pre-tax incomes and inequality, crime rates, suicide rates, and test scores. These results are robust to the use of regression discontinuity estimation, to take account of the possibility of reverse causality. Overall, it seems that Governors behave in a fairly non-ideological manner.本文采用1941-2002年美国各州的面板数据，测度州长党派立场对多类政策设置与经济结果的影响。基于32项衡量指标，民主党与共和党州长执政下的政策设置、社会结果与经济结果竟鲜有实质性差异。政策维度上，民主党州长往往倾向于设置略高的最低工资标准；共和党州长执政时期，监禁率更高，而民主党州长执政时福利领取人数更多。社会与经济结果维度上，民主党州长执政期间的税后收入中位数更高、税后收入不平等程度更低，且失业率也更低。不过，在32个因变量中，有26个的州长党派立场对政策结果与社会福利并无统计学意义上的显著影响。本文未发现州长党派立场在以下维度存在显著差异：税率、福利慷慨程度、政府雇员数量及其薪酬、州财政收入、监禁率、死刑执行率、税前收入与收入不平等程度、犯罪率、自杀率以及考试成绩。为控制反向因果关系的潜在干扰，本文采用断点回归估计法开展稳健性检验，结果显示上述结论具备良好的稳健性。总体而言，州长的施政行为似乎并未表现出显著的意识形态偏向。