Nonpoint source pollution, space, time, and asymmetric information, a deposit refund approach

The incorporation of space allows the establishment of a more precise relationship between a contaminating input, a contaminating byproduct and emissions that reach the final receptor. However, the presence of asymmetric information impedes the implementation of the first-best policy. As a solution to this problem a site specific deposit refund system for the contaminating input and the contaminating byproduct are proposed. Moreover, the utilization of a successive optimization technique first over space and second over time enables definition of the optimal intertemporal site specific deposit refund system.nonpoint source pollution; spatial economics; deposit refund system; asymmetric information

Two Necessary Conditions for Strategy-Proofness: on What Domains are they also Sufficient?

A social choice function may or may not satisfy a desirable property depending on its domain of definition. For the same reason, different conditions may be equivalent for functions defined on some domains, while different in other cases. Understanding the role of domains is therefore a crucial issue in mechanism design. We illustrate this point by analyzing the role of different conditions that are always related, but not always equivalent to strategy-proofness. We define two very natural conditions that are necessary for strategy-proofness: monotonicity and reshuffling invariance. We remark that they are not always sufficient. Then, we identify a domain condition, called intertwinedness, that ensures the equivalence between our two conditions and that of strategy-proofness. We prove that some important domains are intertwined: those of single-peaked preferences, both with public and private goods, and also those arising in simple models of house allocation. We prove that other necessary conditions for strategy-proofness also become equivalent to ours when applied to functions defined on intertwined domains, even if they are not equivalent in general. We also study the relationship between our domain restrictions and others that appear in the literature, proving that we are indeed introducing a novel proposal.strategy-proofness, reshuffling invariance, monotonicity, intertwined domains

Single-dipped preferences

We characterize the set of all individual and group strategy-proof rules on the domain of all single-dipped preferences on a line. For rules defined on this domain, and on several of its subdomains, we explore the implications of these strategy-proofness requirements on the maximum size of the rules' range. We show that when all single-dipped preferences are admissible, the range must contain two alternatives at most. But this bound changes as we consider different subclasses of single-dipped preferences: we provide examples of subdomains admitting strategy-proof rules with larger ranges. We establish exact bounds on the maximal size of strategy-proof functions on each of these domains, and prove that the relationship between the sizes of the subdomains and those of the ranges of strategy-proof functions on them need not be monotonic. Our results exhibit a sharp contrast between the structure of strategy-proof rules defined on subdomains of single-dipped preferences and those defined on subsets of single-peaked ones.strategy-proof, group strategy-proof, binary range rules, single-dipped

Individual versus group strategy-proofness: when do they coincide?

A social choice function is group strategy-proof on a domain if no group of agents can manipulate its final outcome to their own benefit by declaring false preferences on that domain. Group strategy-proofness is a very attractive requirement of incentive compatibility. But in many cases it is hard or impossible to find nontrivial social choice functions satisfying even the weakest condition of individual strategy-proofness. However, there are a number of economically significant domains where interesting rules satisfying individual strategy-proofness can be defined, and for some of them, all these rules turn out to also satisfy the stronger requirement of group strategy-proofness. This is the case, for example, when preferences are single-peaked or single-dipped. In other cases, this equivalence does not hold. We provide sufficient conditions defining domains of preferences guaranteeing that individual and group strategy-proofness are equivalent for all rules defined on theStrategy-proofness, Group strategy-proofness, k-size strategy-proofness, Sequential inclusion, Single-peaked preferences, Single-dipped preferences, Separable preferences.

Group strategy-proof social choice functions with binary ranges and arbitrary domains: characterization results

We define different concepts of group strategy-proofness for social choice functions. We discuss the connections between the defined concepts under different assumptions on their domains of definition. We characterize the social choice functions that satisfy each one of them and whose ranges consist of two alternatives, in terms of two types of basic properties.Social choice functions, Binary ranges, group strategy-proofness, xy-monotonicity, xy-based rules.

Group strategy-proof social choice functions with binary ranges and arbitrary domains: characterization results

JEL Classification Number: D71.We define different concepts of group strategy-proofness for social choice functions. We discuss the connections between the defined concepts under different assumptions on their domains of definition. We characterize the social choice functions that satisfy each one of them and whose ranges consist of two alternatives, in terms of two types of basic properties.We would like to thank the comments of Walter Bossert and Luis Corchón. Salvador Barberà gratefully acknowledges support from the Spanish Ministry of Science and Inno- vation through grant "Consolidated Group-C" ECO2008-04756, and by the Generalitat de Catalunya, Departament d'Universitats, Recerca i Societat de la Informació through the Distinció per a la Promoció de la Recerca Universitària, grant SGR2009-0419 and the Barcelona GSE Research Network. Dolors Berga acknowledges the support of the Spanish Ministry of Science and Innovation through grant SEJ2007-60671 and of Generalitat de Catalunya, through grant SGR2009-0189. She also acknowledges the Research Recogni- tion Programme of the Barcelona GSE. Bernardo Moreno acknowledges nancial support from the Spanish Ministry of Science and Innovation through grant ECO2008-03674.Peer reviewe

On two basic properties of equilibria of voting with exit

We consider the problem of a society whose members must choose from a finite set of alternatives. After knowing the chosen alternative, members may reconsider their membership. Thus, they must take into account, when voting, the effect of their votes not only on the chosen alternative but also on the final composition of the society. We show that, under plausible restrictions on preferences, equilibria of this two-stage game satisfy stability and voter's sovereignty.

A Maximal Domain for Stragegy-proof and No-vetoer Rules in the Multi-object Choice Model

April 2011, Revised February 201

Group strategy-proofness in private good economies

Altres ajuts: SGR2014-515 ; SGR2009-0189 ; 2014-SGR-1360; Junta de Andalucia: SEJ4941, SEJ-5980; ECO2011-29355Many salient rules to allocate private goods are not only strategyproof, but also group strategy-proof, in appropriate domains of definition, hence diminishing the traditional conflict between incentives and efficiency. That is so for solutions to matching, division, cost sharing, house allocation, and auctions, in spite of the substantive disparity between these cases. In a general framework encompassing all of them, we prove that the equivalence between the two forms of strategy-proofness is due to an underlying common structure that transcends the many differences between the contexts and the mechanisms for which it holds. (JEL C78, D44, D63, D71, D82)

On Exiting after Voting

We consider the problem of a society whose members must choose from a finite set of alternatives. After knowing the chosen alternative, members may reconsider their membership in the society by either staying or exiting. In turn, and as a consequence of the exit of some of its members, other members might now find undesirable to belong to the society as well. We analyze the voting behavior of members who take into account the effect of their votes not only on the chosen alternative, but also on the final composition of the societyVoting; Committees; Subgame Perfect Equilibirum