Mobile students and graduates react to the institutional framework of higher education and on their turn induce changes in governmental policies. In this article, we are interested in how governmental decisions about the financial regime and the quality level of higher education interact with...

The paper investigates the formation of information sharing communities. The environment is characterized by the anonymity of the contributors and users, as on the Web. Furthermore information exchange is limited to simple recommendations. When preferences differ, it is argued that a community...

The present Paper investigates political constraints that may impair attempts to reform payment schemes of a given profession. When the good produced (e.g. health care) is imperfectly observable by the payer (e.g. health insurance), asymmetries of information limit the possibility to base...

In a previous paper, we showed how a pay-as-you-go social security scheme, based on voluntary contributions, can be an appropriate institution to reach an optimal sharing of risks among generations in the presence of demographic uncertainties. We study here the functioning of such schemes when...

Social security institutions implement intergenerational transfers and distribute risks over time. To compare various social security designs, we study an overlapping generations model with demographic shocks. Production takes place through a neoclassical production function subject to...

An overlapping generations model of social security with productivity and demographic shocks is studied. The authors focus attention on stationary long-run allocations. An allocation is interim optimal if there does not exist another feasible allocation that improves the expected welfare of all...

A set of n objects and an amount M of money is to be distributed among m people. Example: the objects are tasks and the money is compensation from a fixed budget. An elementary argument via constrained optimization shows that for M sufficiently large the set of efficient, envy free allocations...

An effectivity function describes the blocking power of coalitions on subsets of alternatives. Given a preference profile, if any coalition blocks an alternative whenever it can, using its own power and making all of its members better off, only alternatives in the core can be reached. In this...