Stackelberg thresholds in network routing games or the value of altruism

It is well known that the Nash equilibrium in network routing games can have strictly higher cost than the optimum cost. In Stackelberg routing games, where a fraction of flow is centrally-controlled, a natural problem is to route the centrally-controlled flow such that the overall cost of the resulting equilibrium is minimized.We consider the scenario where the network administrator wants to know the minimum amount of centrally-controlled flow such that the cost of the resulting equilibrium solution is strictly less than the cost of the Nash equilibrium. We call this threshold the Stackelberg threshold and prove that for networks of parallel links with linear latency functions, it is equal to the minimum of the Nash flows on links carrying more optimum flow than Nash flow.Our approach also provides a simpler proof of characterization of the minimum fraction that must be centrally controlled to induce the optimum solution.     

A Profile of Poverty in Egypt

This paper presents a profile of poverty in Egypt for 1997. It assesses the magnitude of poverty and its distribution across geographic and socioeconomic groups, provides information on the characteristics of the poor, illustrates the heterogeneity amongst the poor, and helps identify empirical correlates of poverty. This poverty profile is constructed using data from the Egypt Integrated Household Survey (EIHS), which is a nationwide, multiple‐topic household survey. One of the more striking set of findings relates to the differences between the poor and the non‐poor in their educational attainments. Our results indicate a significant literacy and schooling gap between the poor and the non‐poor. On average the poor have 2.6 fewer years of schooling than the non‐poor, and their literacy rate is 27 percent lower than the non‐poor. Our results also indicate that augmenting educational attainment of the poor does not require building more schools, but reducing the poor’s opportunity cost of attending schools and increasing their returns from extra schooling, both suggesting the importance of income generating activities as a policy instrument.     

Bankruptcy and firm finance

This paper analyzes how an enforcement mechanism that resembles a court affects firm finance. The court is described by two parameters that correspond to enforcement costs and the amount of creditor/debtor protection. We provide a theoretical and quantitative characterization of the effect of these enforcement parameters on the contract loan rate, the default probability and welfare. We analyze agents’ incentive to default and pursue bankruptcy and show that when the constraints that govern these decisions bind, the enforcement parameters can have a sharply non-linear effect on finance. We also compute the welfare losses of “poor institutions” and show that they are non-trivial. The results provide guidance on when models which abstract from enforcement provide good approximations and when they do not.