D choice models of aggregate demand, such as the random coefficients logit, can handle large differentiated products categories parsimoniously while still providing flexible substitution patterns. However, the discrete choice assumption may not be appropriate for many categories in which we expect consumers may purchase more than one unit of the selected item. We derive the aggregate demand sys...

This paper studies the optimal design of second-best corrective regulation, when some agents or activities cannot be perfectly regulated. We show that policy elasticities and Pigouvian wedges are sufficient statistics to characterize marginal welfare impact regulatory policies in a large class environments. is determined by subset elasticities: leakage elasticities, value relaxing constraints. ...

This book develops new convex geometric methods for studying factorization and extensively generalizes positive bases in Euclidean space.