Unemployment in the OECD since the 1960s. Do we really know?

Nickell, Nunziata and Ochel [Economic Journal, 2005] argue that unemployment rates cointegrate with labour market institutions in a panel of OECD countries. This paper reproduces their Maddala-Wu panel cointegration test and shows that this test is only valid when (i) the number of countries tends to infinity and (ii) the underlying country-specific cointegration tests are independent. Their finding of cointegration does not survive when small sample properties and heterogeneous cross-sectional dependencies are taken into account. This suggests that the estimated impact of institutions on unemployment is spurious.