We study the competitive forces which shaped ideological diversity in the US press in the early twentieth century. We find that households preferred like-minded news and that newspapers used their political orientation to differentiate from competitors. We formulate a model of newspaper demand,...

We examine the relationship between concentration and price dispersion using variation induced by a merger in the Canadian mortgage market. Since interest rates are determined through a search and negotiation process, consolidation weakens consumers' bargaining positions. We use reduced-form...

We formally characterize predatory pricing in a modern industry-dynamics framework that endogenizes competitive advantage and industry structure. As an illustrative example we focus on learning-by-doing. To disentangle predatory pricing from mere competition for efficiency on a learning curve we...

We analyze the optimal policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and firms choose among alternative mergers. In our model, the optimal policy of an antitrust authority that seeks to maximize expected consumer surplus imposes a tougher...

We collect a new dataset on capital punishment in the US and we propose a test of racial bias based upon patterns of sentence reversals. We model the courts as minimizing type I and II errors. If trial courts were unbiased, conditional on defendants race the error rate should be independent of...

I explore the association between regional variations in physician behavior and the geographical scope of malpractice standards of care. I estimate a 30-50 percent reduction in the gap between state and national utilization rates of various treatments and diagnostic procedures following the...