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...

This paper introduces the concepts of time-specific weak and strong cross section dependence. A double-indexed process is said to be cross sectionally weakly dependent at a given point in time, t, if its weighted average along the cross section dimension (N) converges to its expectation in...

The Paycheck Protection Program (PPP) aimed to quickly deliver hundreds of billions of dollars of loans to small businesses, with the loans administered via private banks. In this paper, we use firm level data to document the demand and supply of PPP funds. Using an instrumental variables...