This paper investigates if the euro's effect on euro-area trade differs across trade sectors and across country pairs, and to what degree heterogeneity matters for estimating the aggregate euro effect. Time-varying latent variables, which are specific to each sector in each country pair, control...

The introduction of hospital reimbursement based on diagnosis related groups (DRG) in 2004 has been a conspicuous attempt to increase hospital efficiency in the German health sector. In this paper changes of hospital efficiency, quantified as a Malmquist index decomposition in pure technical...

In panel data econometrics the Hausman test is of central importance to select an e±cient estimator of the models' slope parameters. When testing the null hypothesis of no correlation between unobserved heterogeneity and observable explanatory variables by means of the Hausman test model...