This paper analyzes strategy-proof collective choice rules when individuals have single-crossing preferences on a finite and ordered set of social alternatives. It shows that a social choice rule is anonymous, unanimous, and strategy-proof on a maximal single-crossing domain if and only if it is...

This paper provides necessary and sufficient conditions for the existence of a pure strategy Bertrand equilibrium in a model of price competition with fixed costs. It unveils an interesting and unexplored relationship between Bertrand competition and natural monopoly. That relationship points...

In the analysis of group identification, Kasher and Rubinstein (1997), Logique Analyse 160, 385-395, have shown that any method to aggregate the opinions of a group of agents about the individuals in the group that posses a specific attribute, such as race, nationality, profession, etc., must be...

This paper considers a model of (consensual) democracy where political parties engage first in electoral competition, and they share policy-making power afterward according with the votes gathered in the election. The paper uncovers the difficulties to guarantee stability in this institutional...

From a theoretical viewpoint, political budget cycles (PBC) arise in equilibrium when rational voters are imperfectly informed about the incumbent's competency and the incumbent enjoys discretionary power over the budget. This paper focuses on the second condition, examining how executive...

In online social networks, social information, i.e., content generated and shared by users (e.g., past purchases), can be a substitute for sponsored advertising, which constitutes the network's main source of revenue. When will social information be let to spread freely over the platform? We...

In online social networks, social information, i.e., content generated and shared by users (e.g., past purchases), can be a substitute for sponsored advertising, which constitutes the network’s main source of revenue. When will social information be let to spread freely over the platform? We...