Contracts, cost sharing and consistency

Under a contract, agents are not only held to honor the allocation as prescribed by a cost sharing mechanism but also a full description of allocated units and costs once production falls short. For agents leaving the cost sharing problem by taking their demanded units and prepaying the corresponding bill, a contract allows for a reformulation of the cost sharing problem to serve the remaining agents. Consistency requires invariance of cost shares relative to any such reduced cost sharing problem. Under consistency, the proportional mechanisms uniquely satisfy additivity and positivity of cost shares. Exchanging positivity by equal treatment characterizes the set of mechanisms which propose proportional shares for only those agents in the maximal indifference set for some preordering on the rest of nonnegative numbers. This includes egalitarian and average cost sharing. The latter is further characterized by the properties linearity. Under R-consistency, a mechanism is supported by at least one reasonable contract, which meets upperbounds. The class of additive and R-consistent mechanisms is isomorphic to the class of consistent and monotonic rationing methods. Consequently serial cost sharing is R-consistent, whereas Shapley-Shubik is not. Examples are given how the extensive literature on consistent monotonic rationing can be inferred to study and characterize cost sharing mechanisms.

A noncooperative view on two consistent aiport cost sharing rules

This paper provides a noncooperative understanding of the nucleolus and the egalitarian allocation for airport cost problems. We find that every Nash equilibrium of the noncooperative game has the nucleolus as outcome while the egalitarian allocation is just one of the Nash outcomes.airport games, egalitarian allocation, nucleolus, Nash outcomes

Cost of sovereign debt and foreign bias in bond allocations

Finance theory suggests that markets where foreign bond portfolio investors overweight their portfolio relative to the prescribed theoretical benchmark should experience higher international risk sharing. Correspondingly, the cost of debt in such markets should be lower compared to markets facing a lower degree of international risk sharing. We empirically examine this prediction using a panel data set of sovereign bond yield spreads and a measure of suboptimal foreign bond portfolio allocations for 50 emerging and ten developed markets. Consistent with theory, our results show higher levels of foreign bond allocations – relative to the theoretical benchmark – are negatively related to the cost of debt. These results have important policy implications as a country’s cost of debt could potentially be lowered by encouraging foreign portfolio investors to hold their optimal allocation

A noncooperative view on two consistent aiport cost sharing rules

This paper provides a noncooperative understanding of the nucleolus and the egalitarian allocation for airport cost problems. We find that every Nash equilibrium of the noncooperative game has the nucleolus as outcome while the egalitarian allocation is just one of the Nash outcomes.This author acknowledges financial support provided by the Project 9/UPV00031.321-15352/2003 of University of the Basque Country and the Project BEC2003-08182 of the Ministry of Education and Science of Spain

Equity Basis Selection in Allocation Environments

The successful formation and long-term stability of a cooperative venture is often linked to the perceived fairness of the associated cost or resource allocation. In particular, the effectiveness of such collaborations can be hampered by the lack of a consensus view on what basis should be used for gauging an allocation’s “fairness.” Standards of equity in traditional cost-sharing applications could be assessed on many dimensions: per capita, per unit of demand, or per unit of revenue, to mention a few. This multiplicity of logically compelling “equity bases” is a feature common to many practical cost-sharing applications. Our analysis shows that features of the allocation environment are capable of explaining a substantial amount of the variation in the equity bases employed in practice and are consistent with the axiomatic principles of collective behavior.cooperative games; cost allocation; equity; probit model

Political Intergenerational Risk Sharing

TIn a stochastic two-period OLG model, featuring an aggregate shock to the economy, ex-ante optimality requires intergenerational risk sharing. We compare the level of time-consistent intergenerational risk sharing chosen by a benevolent government and by an office-seeking politician. In our political system, the transfer of resources across generations is determined as a Markov equilibrium of a probabilistic voting game. Low realized returns on the risky asset induce politicians to compensate the old through a PAYG system. This political system typically generates an intergenerational risk sharing scheme that is (i) larger, (ii) more persistent, and (iii) less responsive to the realization of the shock than the (time consistent) social optimum. This is because the current politician anticipates her transfers to the elderly to be compensated by future politicians through offsetting transfers, and hence overspends. Aging increases the optimal transfer, but surprisingly makes office-seeking politicians more conservative, by increasing the cost for future politicians to compensate the current young.Pension Systems, Markov equilibria, social optimum

Net foreign assets and imperfect pass-through: the consumption real exchange rate anomaly

An unresolved issue in international macroeconomics is the apparent lack of risk-sharing across countries, which contradicts the prediction of models based on the assumption of complete markets. We assess the importance of financial frictions in this issue by constructing an incomplete market model with stationary net foreign assets (NFA) and imperfect pass-through (IPT). In this paper, there is a cost of bond holdings that allows us to incorporate the dynamics of NFA into the risk-sharing condition. On theoretical grounds, our results suggest that the dynamics of NFA may account for the lack of risk-sharing across countries. In addition, the IPT mechanism, by closing the current account channel, does not help to explain this feature of the data. On empirical grounds, we test the risk-sharing condition derived in the paper, and we find that growth factors of consumption and real exchange rates behave in a manner that may be consistent with a significant role for the net foreign asset position.Risk ; International finance

Risk sharing, finance and institutions in international portfolios

We show that international consumption risk sharing is significantly improved by capital flows, especially portfolio investment. Concomitantly, we show that poor institutions hamper risk sharing, but to an extent that decreases with openness. In particular, risk sharing is prevalent even among economies with poor institutions, provided they are open to international markets. This is consistent with the view that the prospect of retaliation may deter expropriation of foreign capital, even in institutional environments where it is possible. This deterrent is anticipated by investors, who act to diversify risk. By contrast, capital flows headed for closed economies with poor institutions are designed and constrained so as to limit the cost incurred in case of expropriation, and thus achieve little risk sharing. Finally, we show this non-linearity continues to be present in the determinants of international capital flows themselves. Institutions are crucial in attracting capital for closed economies, but are barely relevant in open ones. JEL Classification: F21, F30, G15Bank Loans, Cross-Border Investment, diversification, financial integration, Foreign Direct Investment, Portfolio Choice, portfolio investment, Risk Sharing