We introduce a collective experimentation problem where a continuum of agents choose the timing of irreversible actions under uncertainty and where public feedback from the actions arrives gradually over time. The leading application is the adoption of new technologies. The socially optimal...

We introduce a collective experimentation problem where a continuum of agents choose the timing of irreversible actions under uncertainty and where public feedback from the actions arrives gradually over time. The leading application is the adoption of new technologies. The socially optimal...

We study the determination of market power at the firm and industry levels when heterogeneous firms compete for sales to ex ante homogeneous buyers in a market with both directed and random search and free entry of firms that differ in productivity. Search and the distribution of productivity...