Rates of childhood obesity have increased dramatically in the last few decades. Non-causal evidence suggests that childhood obesity is highly persistent over the life cycle. However little is known about the origins of this persistence. In this paper we attempt to answer three questions. First,...

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...