sequential formation of coalitions in games with externalities and fixed payoff division this paper analyzes a sequential game of coalition formation when the division of the coalitional surplus is fixed and the payoffs are defined relative to the whole coalition structure gains from cooperation are represented by a valuation which maps coalition structures into payoff vectors i show that any core stable coalition structure can be attained as a stationary perfect equilibrium of the game if stationary perfect equilibria may fail to exist in general games a simple condition is provided under which they exist in symmetric games furthermore symmetric stationary perfect equilibria of symmetric games generate a coalition structure which is generically unique up to a permutation of the players a general method for the characterization of equilibria in symmetric games is proposed and applied to the formation of cartels in oligopolies and coalitions in symmetric majority games journal of economic literatureclassification numbers c78 c71 1996 academic press inc

intergenerational equity and sustainability abstract this paper explores the limitations of conventional economic analysis of intergenerational problems and examines some of the alternatives suggested in the literature it is argued that proper consideration of future generations has at least three requirements first when future costs and benefits are considered it should be taken into account that they are to be enjoyed by different generations second the sustainability requirement should be adopted this represents an equity commitment to the future and implies the recognition that future generations have the right to nondeteriorated ecological and economic capacity the paper studies the ways in which the recognition of these rights might be incorporated into economic evaluation and management third an appropriate institutional network to enforce the recognition of these rights in decision making processes should be constituted its design and necessary functions are also analyzed

lobbying by ethnic groups and aid allocation we develop a political economic model of foreign aid allocation each ethnic group in the donor country lobbies the government to allocate more aid to its country of origin and the government accepts political contributions from lobby groups initial per capita income of the recipients and those of the ethnic groups are shown to be important determinants of the solution of the political equilibrium we also examine the effects of changes in the degree of corruption aid fatigue and ethnic composition in the donor country on the allocation of aid

endogenous formation of competing partnerships with moral hazard abstract we analyze the formation of competing partnerships as a sequential game with moral hazard within coalitions in a linear cournot model we show that when moral hazard is very severe no partnerships will form however when moral hazard is not too severe the coalition structure may be more concentrated than it is in the absence of moral hazard concerning industry profits in the absence of moral hazard too many coalitions are formed in equilibrium as compared to the efficient outcome but moral hazard may be responsible for an inefficiency of opposite sign

endogenous structures of association in oligopolies the formulation of associations of firms in an oligopoly with linear demand is analyzed as a two stage noncooperative game in the first stage firms form associations in order to decrease their costs and in the second stage they compete on the market examples of associations include r d joint ventures and groups of firms adopting common standards in equilibrium the associations formed exhibit two general features they are asymmetric and inefficient

a theory of endogenous coalition structures consider an environment with widespread externalities and suppose that bind ing agreements can be written we study coalition formation in such a setting our analysis proceeds by defining on a partition function an extensive form bargaining game we establish the existence of a stationary subgame perfect equilibrium for such a game our main results are concerned with the characterization of equilib rium coalition structures we develop an algorithm that generates under certain conditions an equilibrium coalition structure our characterization results are especially sharp for symmetric partition functions in particular we provide a uniqueness theorem and apply our results to a cournot oligopoly journal of economic literature classification numbers c71 c72 c78 d62 q 1999 academic press

unconditional aid and green growth abstract environmentally motivated aid can help developing countries to achieve economic growth while mitigating the impact on emission levels we argue that the usual practice of giving aid conditionally is not effective and we therefore study aid that is given unconditionally our framework is a differential open loop stackelberg game between a fully developed leader country and a developing follower country the leader chooses the amount of mitigation aid given to the follower which the follower either consumes or invests in either costly non polluting capital or cheap high emission capital we show that giving aid conditionally is only rarely effective and if so is based on a forced intertemporal savings effect in all other cases it is ineffective at best and counterproductive at worst moreover we find that the leader gives unconditional mitigation aid only when sufficiently rich or when caring sufficiently about environmental quality if unconditional aid is given in steady state it decreases the steady state level of high emission capital and capital investments in the recipient country as well as the global pollution stock but it has no effect on the levels of non polluting capital and non polluting investments transitional aid accelerates the economic growth of the follower moreover we find that the increase in growth takes place in the non polluting sector

migration and foreign aid when it comes to linkages between migration and the global allocation of foreign development assistance the size of the immigrant population from a recipient country residing in a donor country is an important determinant of dyadic aid commitments two complementary hypotheses probe this relationship first donors use foreign aid to achieve their broader immigration goals targeting migrant sending areas to increase development and decrease the demand for entry into the donor country second migrants already residing in the donor country mobilize to lobby for additional aid for their homeland empirical tests on a large sample of country pairs made up of twenty two donors and more than 150 recipients over the period 1993 to 2008 show robust support for these hypotheses

can process conditionality enhance aid effectiveness the role of bureaucratic interest and public pressure can process conditionality enhance poverty reduction in developing countries we address this question in a political economic framework with political distortions on the recipient and the donor side process conditionality is a useful tool only if the international financial institutions hold all necessary information to assess the political situation in recipient countries and to select the true representatives of the poor into a participatory process if they do not hold this information or if bureaucratic interests reduce their incentive to acquire this information process conditionality loses its effectiveness

choosing to target what types of countries get different types of world bank projects well governed countries are more likely to make use of foreign aid for the purposes of economic development and poverty alleviation therefore if aid agencies are providing funds for the sake of development these countries should receive more aid and categorically different types of aid as compared with poorly governed countries in poorly governed countries aid should be given in forms that allow for less discretion using an original data set of all world bank projects from 1996 to 2002 the author distinguishes programmatic projects from investment projects and national from subnational investment projects if the world bank allows more discretion in well governed countries then it will choose to provide programmatic and national aid for these recipients the author presents evidence that the world bank provides a larger proportion of national investment lending in better governed countries with regard to programmatic lending he finds mixed evidence among counties eligible for international development association ida aid good governance surprisingly is associated with a lower proportion of programmatic aid whereas for international bank for reconstruction and development ibrd borrowers good governance is associated with a higher proportion the author subjects these results to a number of robustness checks although he confirms the existing result in the literature that the world bank provides larger overall amounts of aid to better governed countries his examination of the disaggregated data leads to questioning whether both lending wings of the world bank are designing aid programs in the most prodevelopment way possible

estimating aid allocation criteria with panel data in 1990 the net amount of economic aid or official development assistance to all recipients from all multilateral and bilateral sources was about 62 billion an amount that exceeded the gdps of greece and portugal despite the size of this yearly transfer there has been no rigors modeling and estimation of the criteria by which it occurs as a result there is little agreement about the extent to which oda is allocated according to the needs of the recipient countries the purpose of this paper is to develop a rigorous theoretical model of oda allocation that can be used to provide consistent estimates of the importance of recipient needs copyright 1994 by royal economic society

competition for aid and trade policy this paper considers the optimal allocation of a given amount of foreign aid between two recipient countries it is shown that given consumer preferences a country following a more restrictive trade policy would receive a smaller share of the aid if the donor country maximises its own welfare in allocating aid if on the other hand the donor country allocates aid in order to maximize the sum of the welfare of the two recipient countries the result is just the opposite finally we analyze the situation where the recipient countries compete with each other for the given amount of aid it is shown that this competition tends to lower the level of optimal tariffs in the recipient countries

ecological thresholds a survey abstract the existence of ecological discontinuities and thresholds has been recognised by ecological economics as a key feature to take into account in the study of environment economy interactions this paper reviews some theoretical developments and empirical studies dealing with ecological phenomena involving non linear dynamics the literature about this issue reveals that there is abundant evidence of discontinuities and threshold effects as the consequence of human perturbations on ecological systems however due to the complexities involved the predictive capacity of ecology is limited and large uncertainties still remain

equilibrium binding agreements abstract we study equilibrium binding agreements the coalition structures that form under such agreements and the efficiency of the outcomes that result we analyze such agreements in a context where the payoff to each player depends on the actions of all other players thus a game in strategic form is a natural starting point unlike the device of a characteristic function explicit attention is paid to the behavior of the complementary set of players when a coalition blocks a proposed agreement a solution concept and its applications are discussed journal of economic literature classification numbers c70 c71

the limits of monopolization through acquisition we address the question of whether competitive acquisition of firms by their rivals can result in complete or partial monopolization of a homogeneous product industry this question is modeled in terms of two distinct three stage noncoopera tive games analysis of subgame perfect pure strategy nash equilibria of these games discloses that under simplifying assumptions monopolization of an industry through acquisition is limited to industries with relatively few firms partial monopolization is either limited in scope or can be completely eliminated by prohibiting any owner from acquiring over 50 percent of the firms in the industry

an analysis of risks for biodiversity under the dpsir framework abstract this paper reviews definitions and uses of the driving forces pressures state impacts responses dpsir framework and argues that it is a relevant tool for structuring communication between scientists and end users of environmental information while it is inappropriate as an analytical tool an apparently deterministic causal description of environmental issues inevitably downplays the uncertainty and multiple dimensions of causality inherent in complex environmental and socio economic systems consequently the paper comoplements and reframes dpsir using a complex system methodology based on the distinction between four spheres of sustainability environmental economic social and political and the analysis of their functioning and relationships the pair wise interface aspects are characterised through investigation of the demands and supply of each sphere relative to the others within the resulting conceptual framework each of the five d p s i and r concepts are specified for application in integrative analysis of relationships between policy society economy and biodiversity in one of the world s largest european integrated research projects on biodiversity alarm

threshold effects and incentives for the conservation of biodiversity biological diversity is a central component of the stock of natural capital on which all economic development is based other things being equal loss of biologically diversity implies loss of development potential and its conservation through sustainable use or outright protection implies the protection of that potential one characteristics of biodiversity loss of especial importance is that biodiversity loss more than any other current environmental problem is associated with ecological threshold effects the paper explores the implication of this characteristics for the properties of a biodiversity conservation strategy

endogenous formation of research coalitions with spillovers abstract we examine the endogenous formation of research coalitions with high spillovers among symmetric firms members of a research coalition set their r and d investments in order to maximize the aggregate profits of members of their coalition the exclusive membership rule supports a more concentrated coalition structure and thus leads to higher industry r and d investments for high spillovers than the open membership rule does however due to free riding problems the grand research coalition which is the socially efficient outcome is rarely an equilibrium outcome under either rule our results suggest that government subsidies to research consortia for basic research with high spillovers can improve social welfare by encouraging wider participation to a research consortium that is by alleviating free rider problems in coalition formation from a more theoretical viewpoint our results on stable coalition structures are applicable to a wide variety of economic coalitions with positive externalities

exploring recipient preferences and allocation mechanisms in the distribution of development aid this study uses incentive compatible techniques to obtain valuations of 14 common poverty reduction interventions from probable aid recipients recipients valuations for these interventions are

stable coalition structures with open membership and asymmetric firms i study games of coalition formation with open membership where firms form associations in order to decrease their costs before competing on the market according to previous analyses only the grand coalition forms at the nash equilibrium of such games i show that this result hinges on the assumption of symmetric firms i therefore introduce asymmetric firms in a game where only two associations can form i demonstrate that there exists a coalition proof nash equilibrium coalition structure in this game and that when the equilibrium involves two associations all the members of an association have a higher taste for this association than all nonmembers do journal of economic literature classification numbers c70 c72 l13

moral hazard and risk spreading in partnerships partnerships provide a classic example of the tradeoff between risk spreading and moral hazard the degree to which firms choose to spread risk and sacrifice efficiency incentives depends upon risk preferences for which data are typically unavailable we use a unique dataset on medical group practice to investigate this tradeoff risk aversion leads to compensation arrangements which spread risk through greater sharing of revenues we find that compensation arrangements with greater degrees of revenue sharing significantly reduce physician effort the results imply that changing the method of physician payment from fee for service to capitation will dramatically reduce physician effort

why conditional aid does not work and what can be done about it abstract this paper studies a simple reform that introduces ex post incentives for the donor to reward good policies contrary to existing practices instead of committing aid to each recipient ex ante and making aid conditional on reform the donor centralizes the disbursement decision by committing aid to a group of countries the actual amount disbursed to each individual country would depend on its relative performance this explicit linkage of the allocation and disbursement decisions has two important advantages as compared to present practices first it raises the opportunity cost of disbursing aid ex post thereby giving the donor stronger incentives to reward good policies second competition among recipients allows the donor to make inferences about common shocks which otherwise conceal the recipient s choice of action this enables the donor to give aid more efficiently

the public and private provision of pure public goods and the distortionary effects of income taxation a political economy approach a pure public good is provided by the government and the voluntary contri butions of two types of households the government finances its contribution by means of income taxation the latter has distortionary effects a third type of household never makes contributions we analyse the effects of changes in the income tax rate on a the pro vision of the public good b the private contributions of the households and c changes in the distribution of income and welfare between contributing and non contributing households we derive a simple and testable condition under which the lowering of the income tax entails a pareto improvement jel classification h23 h24 h41 la fourniture privie et publique de biens publics purs et les effets de distorsion de l imp6t sur les revenus une approche en terme d conomie politique un bien public pur est fourni par le gouvernement et par des contributions volontaires de deux types de m6nages le gouvernement finance sa contribution par un imp6t sur le revenu qui a des effets de distorsion un troisi6me type de menages ne contribue d aucune maniere on examine les effets de changements dans le taux d imposition du revenu sur a la fourniture du bien public b les contributions privees des menages c les changements dans la distribution du revenu et du bien etre entre les menages qui contribuent et ceux qui ne contribuent pas on derive une condition simple et verifiable qui assure qu une reduction d imp6t sur le revenu va engendrer une amelioration au sens de pareto

can poor countries lobby for more us bilateral aid summary this article explores if countries can lobby the us government for the allocation of us bilateral foreign aid we consider an informational lobby model where lobbying has two effects first a direct effect by informing us policymakers about their countries needs second an indirect effect on policymakers by informing them about common interests in economic or geopolitical terms the lobbyist thus influences the decisions about the allocation of aid resources we estimate the effect of the recipient country s lobbying agents in obtaining foreign aid the econometric results show that lobbying positively affects the amount of bilateral aid received

towards an ecological economics of sustainability abstract persistent disagreement both as to the interpretation to be given to sustainability and as to the relation between ecological and economic sustainability has hindered the development of an ecological economics of sustainable resource use this paper identifies the main concepts of sustainability deriving from the two disciplines in order to explore the difference implied by an ecological approach to the problem it is argued that present economic and ecological approaches are largely disjoint and that they address basically different phenomena by combining the efficiency requirements of what is usually thought of as economic sustainability with the stability requirements of an ecological approach it is shown that an intertemporally efficient allocation of resources that satisfies the conditions for constant levels of consumption is not necessary to assure ecological sustainability ecological sustainability requires that the allocation of economic resources should not result in the instability of the economy environment system as a whole

partnerships as insurance devices theory and evidence we model partnerships as mutual insurance associations in which individuals band together to insure themselves against idiosyncratic shocks to their human capital as with most forms of insurance this generates a tradeoff between efficiency and risk sharing since partners keep only a fraction of the profits they generate they will supply less than optimal effort we show that in equilibrium participants in larger partnerships keep a smaller share of their own proceeds we test and confirm this prediction using a sample of partners in law firms

endogenous formation of coalitions the formation of coalitions is a fundamental problem in game theory by a coalition is meant a group of players e g economic or political agents which decide to act together as one unit relative to the rest of the players this includes the instances of syndicates unions cartels blocks political parties parliamentary coalitions etc we would like to emphasize that forming a coalition does not eliminate the individual players as decision makers in all interactions with the other players coalition members act as one unit it may be useful to think of a representative agent taking their place 2 however this arrangement will continue only as long as each player finds it desirable to act this way further bargaining occurs among the members of each coalition on how to divide what they obtained together thus the existence of coalitions implies that the interactions among the players will be conducted on two levels first among the coalitions and second within each coalition most of the existing models in economics and game theory assume that the coalition structure is given exogenously instead we try here to obtain it as an endogenous outcome of our model namely we want to be able to predict which coalitions will in fact form in each given situation 3 our theory combines two kinds of game theoretic concepts value and stability the basic idea is first to evaluate the players prospects in the various coalition structures and then based on these values to find which ones are stable we will call this value coalition structure value or cs value for short the reason we are considering coalition structures i e partitions of the set of players into disjoint coalitions rather than just coalitions is that in general players may find it to their advantage to join forces in some situations and to act separately in others all depending on the way the other participants are organized this implies that both the value and the stability concepts should depend on the entire coalition structure the cs value we analyze in this paper was first developed by owen 7

on the provision of official and private foreign aid abstract the provision of official relative to private foreign aid varies considerably between donor countries we explain the variations in terms of country size household composition income distribution and the government s ability to commit to aid and derive inter alia the results 1 official aid crowds out private aid 2 total aid and official aid collected from each household are lower in more populous countries 3 total aid is lower if i the distribution of income favors the more altruistic households and ii the government can credibly commit to a certain level of aid evidences suggest that the theoretical results can explain stylized facts

the vermont common assets trust an institution for sustainable just and efficient resource allocation both private and public sectors have failed to adequately provide critical ecosystem goods and services or an equitable distribution of wealth and income to address this problem the vermont legislature is considering the creation of a vermont common assets trust vcat that would make the state s atmosphere aquifers and other resources created by nature or by society as a whole the common property of all vermonters present and future under the trust a board of trustees would have the legal obligation to manage these assets for the benefit of all vermonters including future generations this paper first explains why certain resources are likely to be managed more sustainably fairly and efficiently as common property than as private property it then discusses mechanisms for integrating assets into the trust estimates of potential revenue from a vcat suggest that it could eliminate the state budget deficit contribute to a better distribution of wealth and resources and help address critical ecological problems survey results suggest that a vcat is politically feasible the vcat promises to be an important pilot project that could later be scaled up to a national or global level

aid and migration substitutes or complements this paper investigates the impact of aid on migration and identifies two channels bilateral aid influences migration by enhancing the information about labor market conditions in the destination country attraction effect total aid correlates with migration through increasing expenditure financing and hence wages in countries of origin push effect we compute the critical level of income above which emigration and income are substitutes which is about us 7 300 per capita in ppp 2000 prices for example brazil or russia we argue that for countries below this threshold there is a trade off between aid and migration policies a tightening of the migration policy is equivalent to a reduction of the level of aid by about 24 a comparison of skilled and unskilled migrations shows that the former are more sensitive to the attraction effect than the latter

politics and the effectiveness of foreign aid abstract critics of foreign aid programs have long argued that poverty reflects government failure in this paper i test predictions for aid effectiveness based on an analytical framework that relates aid effectiveness to political regimes i find that aid does not significantly increase investment nor benefit the poor as measured by improvements in human development indicators but it does increase the size of government the impact of aid does not vary according to whether recipient governments are liberal democratic or highly repressive but liberal political regimes and democracies ceteris paribus have on average 30 lower infant mortality than the least free regimes this may be due to greater empowerment of the poor under liberal regimes even though the political elite continues to receive the benefits of aid programs an implication is that short term aid targeted to support new liberal regimes may be a more successful means of reducing poverty than current programs

aid trade and migration how do bilateral flows interact this paper takes as its point of departure the european commission s position set out in 2005 which laid clear emphasis on aid and trade as tools for controlling immigration we attempt to subject this position to empirical investigation we exploit data on bilateral aid trade and migration flows between developed and developing countries for the period 2000 10 adopting an instrumental variable approach to address the endogeneity issue due to potential simultaneity bias our results establish that increasing aid and trade with developing countries is likely to fail to contain immigration at least in the short run the pattern of results is consistent with the hypothesis that promoting development in migrant sending countries or cooperating with such countries to control migration outflows is not sufficient to lessen immigration increasing visa restrictions and controls at borders is generally controversial still the results imply that policymakers cannot attain their short term immigration goals with the so called smart solutions of aid and trade

the impact of foreign aid on migration revisited abstract while policymakers hope to stem migration flows by giving foreign aid existing empirical evidence points in the opposite direction by loosening budget constraints aid tends to encourage people to emigrate in this paper we revisit the aid migration link using a substantially extended and adjusted econometric approach based on a gravity model of international migration in contrast to the previous literature we obtain evidence of a negative relationship between the total aid a country receives and emigration rates this even holds for the poorer part of recipient countries which suggests that the budgetary constraint channel does not play a significant role in shaping migration decisions the most plausible explanation for these contrasting results is that unlike in previous studies we use migrant flows rather than migrant stocks as the dependent variable in substantive terms the limited importance of the budgetary constraint channel might reflect that positive welfare effects of foreign aid tend to manifest themselves in improved public services for the poor rather than higher incomes which is in line with the reorientation of foreign aid towards social sectors under the millennium development goals

foreign aid and the question of fungibility this paper analyzes whether the foreign assistance provided for specific categories of expenditure is shifted among them contrary to the wishes of donors it also considers whether aid reduces the tax effort of recipient governments econometric results are presented for the dominican republic that show that the fungibility of aid has resulted in a thwarting of the intentions of donors an attempt is made to account for the observed differences in behavior of individual countries in altering expenditures copyright 1993 by mit press

stable coalition structures with externalities this paper argues that the sign of external effects of coalition formation provides a useful organizing principle in examining economic coalitions in many interesting economic games coalition formation creates either negatie externalities or posi tie externalities for nonmembers examples of negative externalities are research coalitions and customs unions examples of positive externalities include output cartels and public goods coalitions i characterize and compare stable coalition structures under the following three rules of coalition formation the open