Browsing by Subject "Maskin monotonicity"

Now showing 1 - 3 of 3

Open Access
Computational implementation
(Review of Economic Design, 2022-12) Barlo, M.; Dalkıran, Nuh Aygün
Following a theoretical analysis of the scope of Nash implementation for a given mechanism, we study the formal framework for computational identification of Nash implementability. We provide computational tools for Nash implementation in finite environments. In particular, we supply Python codes that identify (i) the domain of preferences that allows Nash implementation by a given mechanism, (ii) the maximal domain of preferences that a given mechanism Nash implements Pareto efficiency, (iii) all consistent collections of sets of a given social choice correspondence (SCC), the existence of which is a necessary condition for Nash implementation of this SCC, and (iv) check whether some of the well-known sufficient conditions for Nash implementation hold for a given SCC. Our results exhibit that the computational identification of all collections consistent with an SCC enables the planner to design appealing mechanisms. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Open Access
Do impossibility results survive in historically standard domains?
(2008) Gürer, Ebru
One of the major assumptions common to all impossibility results in social choice theory is that of ”full” or rich enough domain. Thus, a major stream of attempts has focused on how to restrict the domains of social choice functions in order to escape impossibilities, without paying much attention to the question of whether there exist actual societies with such restricted domains of preference profiles, however. The notion of an unrestricted domain is based on the assumption that the individuals form their preferences independent of each other. If one replaces this assumption by one under which individual preferences are clustered around a ”social norm” in a unipolar standard society, the question of how this kind of restricted domain restriction influences the existence of a Maskin monotonic, surjective and nondictatorial social choice function becomes important. We employ the so-called Manhattan metric to measure the degree of how clustered a society around a social norm is. We then try to characterize what degrees of clustering around a social norm allow us to escape impossibility results, in an attempt to shed some light on the question of whether impossibilities in social choice theory arise from assuming the existence of historically impossible societies.
Open Access
Implementation with a sympathizer
(Elsevier B.V., 2022-12-15) Altun, O. A.; Barlo, M.; Dalkıran, Nuh Aygün
We study Nash implementation under complete information with the distinctive feature that the planner knows neither individuals’ state-contingent preferences (payoff states) nor how they correspond to the states of the economy on which the social goal depends. Our main question is whether or not the planner can extract only the essential information about individuals’ underlying preferences and simultaneously implement the given social goal. Our setup is especially relevant when the planner cannot use mechanisms asking for the full revelation of the payoffs states due to privacy and political correctness concerns or non-disclosure and confidentiality agreements. In economic environments with at least three individuals, we show that the planner may Nash implement a social goal while extracting only the essential information about the payoff states from the society whenever this goal has standard monotonicity properties and one of the individuals whose identity is not necessarily known to the planner and the other individuals, is a sympathizer. Vaguely put, such an agent is inclined toward the truthful revelation of the essential information about how states of the economy are associated with individuals’ preferences, while he is not inclined to reveal the realized ‘true’ state of the economy. Then, in every Nash equilibrium of the mechanism we design, all individuals truthfully disclose the same essential information about the payoff states.