|
| ||
|
|
||
Choice Function (choice + function)
Kinds of Choice Function Selected AbstractsThe Limits of ex post ImplementationECONOMETRICA, Issue 3 2006Philippe Jehiel The sensitivity of Bayesian implementation to agents' beliefs about others suggests the use of more robust notions of implementation such as ex post implementation, which requires that each agent's strategy be optimal for every possible realization of the types of other agents. We show that the only deterministic social choice functions that are ex post implementable in generic mechanism design frameworks with multidimensional signals, interdependent valuations, and transferable utilities are constant functions. In other words, deterministic ex post implementation requires that the same alternative must be chosen irrespective of agents' signals. The proof shows that ex post implementability of a nontrivial deterministic social choice function implies that certain rates of information substitution coincide for all agents. This condition amounts to a system of differential equations that are not satisfied by generic valuation functions. [source] Aggregation of ordinal and cardinal preferences: a framework based on distance functionsJOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 3-4 2008Jacinto González-Pachón Abstract In this paper a collective choice function (CCF), formulated within a p -metric distance function framework, is proposed as a generator of several compromise consensuses. Even though, the proposed CCF is not smooth, it is however demonstrated that it can be straightforwardly transformed into easily computable goal programming models. Finally, several cases of individual preferences aggregation are obtained by providing different interpretations of the CCF parameters: ordinal and complete information, ordinal and partial information and a cardinal case through ,pairwise' comparison matrices. Copyright © 2009 John Wiley & Sons, Ltd. [source] Strategy-Proofness and the Tops-Only PropertyJOURNAL OF PUBLIC ECONOMIC THEORY, Issue 1 2008JOHN A. WEYMARK A social choice function satisfies the tops-only property if the chosen alternative only depends on each person's report of his most-preferred alternatives on the range of this function. On many domains, strategy-proofness implies the tops-only property provided that the range of the social choice function satisfies some regularity condition. The existing proofs of this result are model specific. In this paper, a general proof strategy is proposed for showing that a strategy-proof social choice function satisfies the tops-only property when everyone has the same set of admissible preferences. [source] The Limits of ex post ImplementationECONOMETRICA, Issue 3 2006Philippe Jehiel The sensitivity of Bayesian implementation to agents' beliefs about others suggests the use of more robust notions of implementation such as ex post implementation, which requires that each agent's strategy be optimal for every possible realization of the types of other agents. We show that the only deterministic social choice functions that are ex post implementable in generic mechanism design frameworks with multidimensional signals, interdependent valuations, and transferable utilities are constant functions. In other words, deterministic ex post implementation requires that the same alternative must be chosen irrespective of agents' signals. The proof shows that ex post implementability of a nontrivial deterministic social choice function implies that certain rates of information substitution coincide for all agents. This condition amounts to a system of differential equations that are not satisfied by generic valuation functions. [source] Towards a general and unified characterization of individual and collective choice functions under fuzzy and nonfuzzy preferences and majority via the ordered weighted average operatorsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 1 2009Janusz Kacprzyk A fuzzy preference relation is a powerful and popular model to represent both individual and group preferences and can be a basis for decision-making models that in general provide as a result a subset of alternatives that can constitute an ultimate solution of a decision problem. To arrive at such a final solution individual and/or group choice rules may be employed. There is a wealth of such rules devised in the context of the classical, crisp preference relations. Originally, most of the popular group decision-making rules were conceived for classical (crisp) preference relations (orderings) and then extended to the traditional fuzzy preference relations. In this paper we pursue the path towards a universal representation of such choice rules that can provide an effective generalization,for the case of fuzzy preference relations,of the classical choice rules. © 2008 Wiley Periodicals, Inc. [source] ON DETAIL-FREE MECHANISM DESIGN AND RATIONALITY,THE JAPANESE ECONOMIC REVIEW, Issue 1 2005HITOSHI MATSUSHIMAArticle first published online: 23 FEB 200 Mechanism design theory has been criticized, because mechanisms depend on the detail of specification and agents' behaviour relies on strong rationality assumptions. Hence the study of "detail-free" mechanism design with weak rationality is important as a practical theory. This paper emphasizes that, even if we confine our attention to detail-free mechanisms with weak rationality, there exists plenty of scope for the development of new and significant ideas. I describe my recent work along these lines, and argue that stochastic decisions work in large double auction environments, and that moral preferences improve the implementability of social choice functions. [source] | ||||||||||