The paper provides new evidence on the outmigration of foreign-born immigrants. We make use of data from the German Socio-Economic Panel and employ penalised spline smoothing in the context of a Poisson-type Generalised Additive Mixed Model (GAMM), which enables us to incorporate bivariate...

__Abstract__ Crucial inference for the hierarchical linear model concerns the null hypothesis of no random slope. We argue that the usually applied statistical test suffers from the so-called Davies problem, that is, a nuisance parameter is only identified under the alternative. We propose an...