DSpace Collection:
http://hdl.handle.net/2445/12560
2024-03-28T06:47:38ZAxioms for the optimal stable rules and fair-division rules in a multiple-partners job market [WP]
http://hdl.handle.net/2445/185052
Title: Axioms for the optimal stable rules and fair-division rules in a multiple-partners job market [WP]
Author: Domènech i Gironell, Gerard; Núñez, Marina (Núñez Oliva)
Abstract: In the multiple-partners job market, introduced in (Sotomayor, 1992), each firm can hire several workers and each worker can be hired by several firms, up to a given quota. We show that, in contrast to what happens in the simple assignment game, in this extension, the firms-optimal stable rules are neither valuation monotonic nor pairwise monotonic. However, we show that the firms-optimal stable rules satisfy a weaker property, what we call firm covariance, and that this property characterizes these rules among all stable rules. This property allows us to shed some light on how firms can (and cannot) manipulate the firms-optimal stable rules. In particular, we show that firms cannot manipulate them by constantly over-reporting their valuations.
Analogous results hold when focusing on the workers. Finally, we extend to the multiple-partners market a known characterization of the fair-division rules on the domain of simple assignment games.2022-04-20T08:45:19ZStable cores in information graph games [WP]
http://hdl.handle.net/2445/172298
Title: Stable cores in information graph games [WP]
Author: Núñez, Marina (Núñez Oliva); Vidal-Puga, Juan
Abstract: Stable cores in information graph games Abstract: In an information graph situation, some agents that are connected by an undirected graph can share with no cost some information or technology that can also be obtained from a source. If an agent is not connected to an informed player, this agent pays a unitary cost to obtain this technology. A coalitional cost game can be defined from this situation, and the core of this game is known to be non- empty. We prove that the core of an information graph game is a von Neumann-Morgenstern stable set if and only if the graph is cycle- complete, or equivalently if the information graph game is concave. When the graph is not cycle-complete, whether there always exists a stable set is an open question. In this regard, we show that if the information graph consists of a ring that contains the source, then a stable set always exists and it is the core of a related information graph situation where one edge has been deleted.2020-11-23T21:10:53ZContinuous-time Optimal Pension Indexing in Pay-as-You-Go Systems
http://hdl.handle.net/2445/170984
Title: Continuous-time Optimal Pension Indexing in Pay-as-You-Go Systems
Author: Roch, Oriol
Abstract: Ageing population and economic crisis have placed pay-as-you-go pension systems in need of mechanisms to ensure its financial stability. In this paper, we consider optimal indexing of pensions as an instrument to cope with the financial imbalances typically found in these systems. Using dynamic programming techniques in a stochastic continuous-time framework, we compute the optimal pension index and portfolio strategy that best target indexing and liquidity objectives determined by the government. A numerical example is provided to illustrate the results2020-10-02T10:16:14ZIntroducing media in a model of electoral competition with candidate quality
http://hdl.handle.net/2445/163900
Title: Introducing media in a model of electoral competition with candidate quality
Author: Domènech i Gironell, Gerard
Abstract: This work proposes and studies a two candidate model of electoral competition with candidate quality and media. The role of media is to inform voters about the quality of each candidate. We assume that there are two non-strategic media outlets, each one with a different ideal policy (there is a leftist media outlet and a rightist one), and that both of them transmit lower quality for a candidate the further from their ideal policy the policy the candidate proposes is. We also assume that the rightist media outlet has greater coverage, in the sense that it informs neutral voters and voters slightly on the left side of the political spectrum. We study the model under the classical assumption of risk-averse voters. Classical results concerning PSNE generally hold with a "media bias". We extend and characterize in our setting the MSNE found in Aragonés and Xefteris (2012), which sometimes fails to exist in our model.2020-06-02T16:51:56ZAnálisis cuantitativo de productos en España para licuar el patrimonio en la tercera edad: rentas vitalicias e hipotecas inversas
http://hdl.handle.net/2445/152279
Title: Análisis cuantitativo de productos en España para licuar el patrimonio en la tercera edad: rentas vitalicias e hipotecas inversas
Author: Bosch Príncep, Manuela; Claramunt Bielsa, M. Mercè
Abstract: Las recientes reformas del sistema público de pensiones en España tendrán como consecuencia, en la mayoría de los casos, la disminución de los importes de las pensiones de jubilación. Frente a esta situación, parece de sentido común que se contemplen posibilidades de disponer de unos ingresos adicionales a los de la pensión pública. Si se tiene un plazo de tiempo suficiente, una opción es ahorrar con el objetivo de que llegado el momento de la jubilación se haya constituido el capital suficiente. Otra opción para las personas que no tengan margen de maniobra, pero en cambio dispongan de inmuebles, es buscar alternativas que les permitan licuar los inmuebles para conseguir el mismo objetivo.
En este trabajo, centramos la atención en la segunda opción y analizamos dos instrumentos del mercado financiero y asegurador para obtener liquidez a partir de los bienes inmuebles: las rentas vitalicias aseguradas inmobiliarias y las hipotecas inversas. Adicionalmente a la definición y posterior tarificación de cada producto, en este trabajo se incluyen los efectos fiscales, y se realiza una comparativa cuantitativa de la renta resultante para el contratante del producto y sus herederos.2020-03-09T09:05:58ZOn Convexity in Games with Externalities
http://hdl.handle.net/2445/147779
Title: On Convexity in Games with Externalities
Author: Alonso-Meijide, José Mª; Álvarez-Mozos, Mikel; Fiestras-Janeiro, M. Gloria, 1962-; Jiménez-Losada, Andrés
Abstract: We introduce new notions of superadditivity and convexity for games with coalitional externalities. We show parallel results to the classic ones for transferable utility games without externalities. In superadditive games the grand coalition is the most efficient organization of agents. The convexity of a game is equivalent to having non decreasing contributions to larger embedded coalitions. We also see that convex games can only have negative externalities2020-01-14T13:42:50ZAssortative multisided assignment games. The extreme core points [WP]
http://hdl.handle.net/2445/144180
Title: Assortative multisided assignment games. The extreme core points [WP]
Author: Martínez de Albéniz, F. Javier; Rafels, Carles; Ybern, Neus
Abstract: We analyze assortative multisided assignment games, following Sherstyuk (1999) and Martínez-de-Albéniz et al. (2019). In them players’ abilities are complementary across types (i.e. supermodular), and also the output of the essential coalitions is increasing depending on types. We study the extreme core points and show a simple mechanism to compute all of them. In this way we describe the whole core. This mechanism works from the original data array and the maximum number of extreme core points is obtained.2019-11-08T11:20:02ZA new order on embedded coalitions: Properties and Applications
http://hdl.handle.net/2445/131210
Title: A new order on embedded coalitions: Properties and Applications
Author: Alonso-Meijide, José Mª; Álvarez-Mozos, Mikel; Fiestras-Janeiro, M. Gloria, 1962-; Jiménez-Losada, Andrés
Abstract: Given a finite set of agents, an embedded coalition consists of a coalition and a partition of the rest of agents. We study a partial order on the set of embedded coalitions of a finite set of agents. An embedded coalition precedes another one if the first coalition is contained in the second and the second partition equals the first one after removing the agents in the second coalition. This poset is not a lattice. We describe the maximal lower bounds and minimal upper bounds of a finite subset, whenever they exist. It is a graded poset and we are able to count the number of elements at a given level as well as the total number of chains. The study of this structure allows us to derive results for games with externalities. In particular, we introduce a new concept of convexity and show that it is equivalent to having non-decreasing contributions to embedded coalitions of increasing size.2019-04-02T13:49:52ZThe nucleolus of the assignment game. Structure of the family
http://hdl.handle.net/2445/127510
Title: The nucleolus of the assignment game. Structure of the family
Author: Martínez de Albéniz, F. Javier; Rafels, Carles; Ybern, Neus
Abstract: We show that the family of assignment matrices which give rise to the same nucleolus forms a compact join-semilattice with one maximal element. The above family is in general not a convex set, but path-connected.2019-01-22T12:21:22ZStrategic investment decisions under the nuclear power debate in Belgium [WP]
http://hdl.handle.net/2445/125421
Title: Strategic investment decisions under the nuclear power debate in Belgium [WP]
Author: Frutos Cachorro, Julia de; Willeghems, Gwen; Buysse, Jeroen
Abstract: In view of the current nuclear power debate in Belgium, we analyze how uncertainty about a nuclear phase-out, coupled with the implementation of renewable energy subsidies and nuclear taxes, affects investment capacity and productivity decisions by Belgian electricity suppliers. To achieve this goal, considering the key characteristics of the Belgian market, we build a Stackelberg closed-loop (two-stage) equilibrium model in which investment decisions are made in a first stage under uncertainty regarding a nuclear phase-out, and productivity decisions are subsequently made in a second stage in a c ertainty environment. Our analysis indicates that, regardless of subsidies, an increase in the probability of nuclear license extension results in lower levels of investment - primarily in renewable energy -, lower total production and a higher electricity price. We also show that the implementation of renewable energy subsidies reduces the effect of an increase in probability of nuclear license extension on producer’s decisions regarding expanded capacity and on total profits in the market.2018-10-18T09:13:13Z