Consider a researcher estimating the parameters of a regression function based on data for all 50 states in the United States or on data for all visits to a website. What is the interpretation of the estimated parameters and the standard errors? In practice, researchers typically assume that the...

In many areas, practitioners seek to use observational data to learn a treatment assignment policy that satisfies application‐specific constraints, such as budget, fairness, simplicity, or other functional form constraints. For example, policies may be restricted to take the form of decision...

We examine vertical backward integration in a reduced-form model of successive oligopolies. Our key findings are: (i) There may be asymmetric equilibria where some firms integrate and others remain separated, even if firms are symmetric initially; (ii) Efficient firms are more likely to...

In Germany, competitive franchising is increasingly being used to procure passenger railway services that were previously provided by a state monopolist. This paper analyzes 77 tenders that differ with respect to network size, service frequency, contract duration and the proximity to other lines...