How Much Should We Trust Regression-Kink-Design Estimates?

In a Regression Kink (RK) design with a finite sample, a confounding smooth nonlinear relationship between an assignment variable and an outcome variable around a threshold can be spuriously picked up as a kink and result in a biased estimate. In order to investigate how well RK designs handle such confounding nonlinearity, I firstly implement Monte Carlo simulations and then study the effect of fiscal equalization grants on local expenditure using a RK design. Results suggest that RK estimation with a confounding nonlinearity often suffers from bias or imprecision and estimates are credible only when relevant covariates are controlled for

Estimating the effects of nuclear power facilities on local income levels : A quasi-experimental approach

This paper studies how the establishment of Nuclear Power Facilities (NPF) in the 1970s and 1980s has affected local per capita income levels in NPF-located municipalities in Japan by using the synthetic control method (SCM). Eight quantitative case studies using the SCM clarify that the effects of NPF establishment on per capita taxable income levels are highly heterogeneous, but often economically meaningful and in some cases huge: an 11 % increase on average, a 62 % increase in Rokkasho village in 2002 and a 30 % increase in Tomioka town in 2002. On the other hand, a few NPF-located municipalities receive weak or negligible effects from NPF establishment. I also examine the statistical significance of individual treatment effects with several placebo tests and find that the treatment effects of 4 out of the 8 NPF locations are larger than 95% of placebo effects

Universal Early Childhood Education and Adolescent Risky Behavior

The evidence for the effects of early childhood education on risky behavior in adolescence is limited. This paper studies the consequences of a reform of a large-scale universal kindergarten program in Japan. Exploiting a staggered expansion of kindergartens across regions, we estimate the effects of the reform using an event study model. Our estimates indicate that the reform significantly reduced juvenile violent arrests and the rate of teenage pregnancy, but we do not find that the reform increased the high school enrollment rate. We suspect that improved non-cognitive skills can account for the reduction of risky behavior in adolescence