The analysis provides a new explanation for two widespread problems concerning European unemployment policy: the disappointingly small effect of many past reform measures on unemployment, and the political difficulties in implementing more extensive reform programs. We argue that the heart of...

This paper considers the problem of aggregation in the case of large linear dynamic panels, where each micro unit is potentially related to all other micro units, and where micro innovations are allowed to be cross sectionally dependent. Following Pesaran (2003), an optimal aggregate function is...