We develop a model that is a synthesis of the two-sided markets duopoly model of Armstrong (2006) with the nested vertical and horizontal dierentiation model of Gabszewicz and Wauthy (2012), which consists of a linear city with dierent consumer densities on the left and on the right side of the...

We consider a model in which a free daily newspaper distributes news to readers and sells ad-space to advertisers, having private information about its readership. Depending on the type of readers in the market, the newspaper's may have a "plentiful and seeking" audience or a "lacking and...

We study the optimal regulation of a monopolist when intrinsic efficiency (intrinsic cost) and empire building tendency (marginal utility of output) are private information, but actual cost (the difference between intrinsic cost and effort level) is observable. This is a problem of...

We develop a model of general equilibrium with trade ex ante in a context of private and incomplete state verification. Instead of choosing bundles, agents choose lists of bundles out of which the market then selects one bundle for delivery. With agents having subjective expectations about the...

We propose a profit-sharing rule that maximizes sustainability of cartel agreements. This rule is such that the critical discount factor is the same for all the firms. If a cartel applies this rule, then asymmetries among firms may not hinder collusion (contrarily to the typical finding in the...