5,056 research outputs found

    Stable Roommate Problem with Diversity Preferences

    Full text link
    In the multidimensional stable roommate problem, agents have to be allocated to rooms and have preferences over sets of potential roommates. We study the complexity of finding good allocations of agents to rooms under the assumption that agents have diversity preferences [Bredereck et al., 2019]: each agent belongs to one of the two types (e.g., juniors and seniors, artists and engineers), and agents' preferences over rooms depend solely on the fraction of agents of their own type among their potential roommates. We consider various solution concepts for this setting, such as core and exchange stability, Pareto optimality and envy-freeness. On the negative side, we prove that envy-free, core stable or (strongly) exchange stable outcomes may fail to exist and that the associated decision problems are NP-complete. On the positive side, we show that these problems are in FPT with respect to the room size, which is not the case for the general stable roommate problem. Moreover, for the classic setting with rooms of size two, we present a linear-time algorithm that computes an outcome that is core and exchange stable as well as Pareto optimal. Many of our results for the stable roommate problem extend to the stable marriage problem.Comment: accepted to IJCAI'2

    Simple Priorities and Core Stability in Hedonic Games

    Get PDF
    In this paper we study hedonic games where each player views every other player either as a friend or as an enemy. Two simple priority criteria for comparison of coalitions are suggested, and the corresponding preference restrictions based on appreciation of friends and aversion to enemies are considered. It turns out that the first domain restriction guarantees non-emptiness of the strong core and the second domain restriction ensures non-emptiness of the weak core of the corresponding hedonic games. Moreover, an element of the strong core under friends appreciation can be found in polynomial time, while finding an element of the weak core under enemies aversion is NP-hard. We examine also the relationship between our domain restrictions and some sufficient conditions for non-emptiness of the core already known in the literature.Additive separability, Coalition formation, Core stability, Hedonic games, NP-completeness, Priority

    Coalition Formation in Simple Games: The Semistrict Core

    Get PDF
    We consider the class of proper monotonic simple games and study coalition formation when an exogenous share vector and a solution concept are combined to guide the distribution of coalitional worth. Using a multiplicative composite solution, we induce players' preferences over coalitions in a hedonic game, and present conditions under which the semistrict core of the game is nonempty.Coalition Formation, Paradox of Smaller Coalitions, Semistrict Core, Simple Games, Winning Coalitions

    The Amenity Value of Climate to German Households

    Get PDF
    This study uses the hedonic approach to measure the amenity value of climate in Germany. Unlike in earlier research separate hedonic wage and house price regressions are estimated for relatively small geographic areas and formal tests undertaken to determine whether the coefficients describing the impact of climate variables are homogenous across these areas. Evidence suggests that German households are compensated for climate amenities mainly through hedonic housing markets. Given that climate is largely unproductive to industry and few industries spend more on land than labour this is consistent with what theory would predict. Throughout Germany house prices are higher in areas with higher January temperatures, lower July temperatures and lower January precipitation. In East Germany wages are higher in areas with higher January precipitation. The full implicit price of climate variables however is very uncertain.Climate change, Germany, Hedonic pricing

    Formation of Segregated and Integrated Groups

    Get PDF
    A model of group formation is presented where the number of groups is fixed and a person can only join a group if the group’s members approve the person’s joining. Agents have either local status preferences (each agent wants to be the highest status agent in his group) or global status preferences (each agent wants to join the highest status group that she can join). For both preference types, conditions are provided which guarantee the existence of a segregated stable partition where similar people are grouped together and conditions are provided which guarantee the existence of an integrated stable partition where dissimilar people are grouped together. Additionally, in a dynamic framework we show that if a new empty group is added to a segregated stable partition, then integration may occur.Group Formation, Stable Partition, Segregation, Integration

    Computational Complexity in Additive Hedonic Games

    Get PDF
    We investigate the computational complexity of several decision problems in hedonic coalition formation games and demonstrate that attaining stability in such games remains NP-hard even when they are additive. Precisely, we prove that when either core stability or strict core stability is under consideration, the existence problem of a stable coalition structure is NP-hard in the strong sense. Furthermore, the corresponding decision problems with respect to the existence of a Nash stable coalition structure and of an individually stable coalition structure turn out to be NP-complete in the strong sense.Additive Preferences, Coalition Formation, Computational Complexity, Hedonic Games, NP-hard, NP-complete

    The Egalitarian Sharing Rule in Provision of Public Projects

    Get PDF
    In this note we consider a society that partitions itself into disjoint jurisdictions, each choosing a location of its public project and a taxation scheme to finance it. The set of public project is multi-dimensional, and their costs could vary from jurisdiction to jurisdiction. We impose two principles, egalitarianism, that requires the equalization of the total cost for all agents in the same jurisdiction, and efficiency, that implies the minimization of the aggregate total cost within jurisdiction. We show that these two principles always yield a core-stable partition but a Nash stable partition may fail to exist.Jurisdictions, Stable partitions, Public projects, Egalitarianism

    Evaluation of Urban Improvement on the Islands of the Venice Lagoon: A Spatially-Distributed Hedonic-Hierarchical Approach

    Get PDF
    This paper presents a model for the evaluation of environmental and urban improvements on the islands of the Venetian lagoon. The model simulates the changes in residential real estate values using a value function integrated in a geographical database which provides spatial distributions of values changes. The fairly weak market signals, fragmented demand and strong externalities, and the scarcity of market data available do not permit the use of econometric models for value appraisal. Appropriate hedonic-hierarchical value functions are calibrated on the basis of a set of indicators of the characteristics of the buildings and the location. Some applications of the model are illustrated simulating two scenarios of future interventions which are actually being discussed or realised and involving the island of Murano, Burano and S. Erasmo in the Venice Lagoon. The interventions considered are: subway beyond the lagoon connecting Murano with Venice and the mainland, and the solution of “high water” problems on Murano, Burano and S. Erasmo.Public work assessment, Property value, Hierarchical analysis

    Coalition Formation with Local Public Goods and Network Effect

    Get PDF
    Many local public goods are provided by coalitions and some of them have network effects. Namely, people prefer to consume a public good in a coalition with more members. This paper adopts the Drèze and Greenberg (1980) type utility function where players have preferences over goods as well as coalition members. In a game with anonymous and separable network effect, the core is nonempty when coalition feasible sets are monotonic and players' preferences over public goods have connected support. All core allocations consist of connected coalitions and they are Tiebout equilibria as well. We also examine the no-exodus equilibrium for games whose feasible sets are not monotonic.Coalition formation, core, network effect, local public goods
    • …
    corecore