Two-player preplay negotiation games with conditional offers

We consider an extension of strategic normal form games with a phase before the actual play of the game, where players can make binding offers for transfer of utilities to other players after the play of the game, contingent on the recipient playing the strategy indicated in the offer. Such offers transform the payoff matrix of the original game but preserve its non-cooperative nature. The type of offers we focus on here are conditional on a suggested 'matching offer' of the same kind made in return by the receiver. Players can exchange a series of such offers, thus engaging in a bargaining process before a strategic normal form game is played. In this paper we study and analyze solution concepts for two-player normal form games with such preplay negotiation phase, under several assumptions for the bargaining power of the players, such as the possibility of withdrawing previously made offers and opting out from the negotiation process, as well as the value of time for the players in such negotiations. We obtain results describing the possible solutions of such bargaining games and analyze the degrees of efficiency and fairness that can be achieved in such negotiation process

A network-based rating system and its resistance to bribery

We study a rating system in which a set of individuals (e.g., the customers of a restaurant) evaluate a given service (e.g, the restaurant), with their aggregated opinion determining the probability of all individuals to use the service and thus its generated revenue. We explicitly model the influence relation by a social network, with individuals being influenced by the evaluation of their trusted peers. On top of that we allow a malicious service provider (e.g., the restaurant owner) to bribe some individuals, i.e., to invest a part of his or her expected income to modify their opinion, therefore influencing his or her final gain. We analyse the effect of bribing strategies under various constraints, and we show under what conditions the system is bribery-proof, i.e., no bribing strategy yields a strictly positive expected gain to the service provider

The Formation of Jupiter, the Jovian Early Bombardment and the Delivery of Water to the Asteroid Belt: The Case of (4) Vesta

The asteroid (4) Vesta, parent body of the Howardite-Eucrite-Diogenite meteorites, is one of the first bodies that formed, mostly from volatile-depleted material, in the Solar System. The Dawn mission recently provided evidence that hydrated material was delivered to Vesta, possibly in a continuous way, over the last 4 Ga, while the study of the eucritic meteorites revealed a few samples that crystallized in presence of water and volatile elements. The formation of Jupiter and probably its migration occurred in the period when eucrites crystallized, and triggered a phase of bombardment that caused icy planetesimals to cross the asteroid belt. In this work, we study the flux of icy planetesimals on Vesta during the Jovian Early Bombardment and, using hydrodynamic simulations, the outcome of their collisions with the asteroid. We explore how the migration of the giant planet would affect the delivery of water and volatile materials to the asteroid and we discuss our results in the context of the geophysical and collisional evolution of Vesta. In particular, we argue that the observational data are best reproduced if the bulk of the impactors was represented by 1-2 km wide planetesimals and if Jupiter underwent a limited (a fraction of au) displacement.Comment: 31 pages, 11 figures, and 3 tables. Published in the special issue "Planet Formation and the Rise of Life" on the journal Life. arXiv admin note: text overlap with arXiv:1309.139

Non-cooperative games with preplay negotiations

We consider an extension of strategic normal form games with a phase of negotiations before the actual play of the game, where players can make binding offers for transfer of utilities to other players after the play of the game, in order to provide additional incentives for each other to play designated strategies. Such offers are conditional on the recipients playing the specified strategies and they effect transformations of the payoff matrix of the game by accordingly transferring payoffs between players. We introduce and analyze solution concepts for 2-player normal form games with such preplay offers under various assumptions for the preplay negotiation phase and obtain results for existence of efficient negotiation strategies of the players. Then we extend the framework to coalitional preplay offers in N-player games, as well as to extensive form games with inter-play offers for side payments

Received wisdom and beyond: Lessons from fiscal consolidation in the EU

The paper examines consolidation episodes in the EU since 1970 with a view to shedding light on the factors that determine the success or failure of fiscal adjustment. Compared to the existing literature on successful fiscal consolidations we add a number of new dimensions. Two deserve particular attention. Firstly, we explore a broader set of potential ingredients of the recipe for success. In addition to the composition of adjustment, which has extensively been examined in the literature, we consider further elements such as the quality and strength of fiscal governance and the implementation of structural reforms. Secondly, our analysis seeks to differentiate between at least two different types of consolidation episodes, one in which a relatively big fiscal correction is implemented in a short period of time, dubbed 'cold shower' consolidation, as compared to more gradual episodes of adjustment. Such a differentiation is motivated by the conjecture that the recipe for success may be conditional on the type of adjustment chosen. Our analysis broadly confirms the results established in the literature for what concerns (i) the conditions triggering a consolidation episode and (ii) the composition of adjustment, with minor but important qualifications related to the role played by government wages. In addition it provides evidence that well-designed fiscal governance as well as structural reforms improve the odds of both starting a consolidation episode and achieving a lasting fiscal correctionFiscal consolidation, fiscal rules, budgetary procedures, structural reforms, Larch, Turrini

Textile mills in Friuli (XIX-XX century). Building technique analysis and seismic refurbishment

The conservation of industrial architectures and the refurbishment project, must take into account the growing attention to the seismic risk of the built heritage, which the recent events of central Italy have made dramatically current. The different constructive nature and structural behavior of industrial buildings, impose a different approach, combining the new functional needs - and therefore the safety of the building - with its conservation as a testimony for future generations. The work focuses the Friulian textile industry buildings (XIX and XX century), studying their constructive techniques and identyfing some guidelines for the refurbishment

Received wisdom and beyond: Lessons from fiscal consolidations in the EU

The paper examines consolidation episodes in the EU since 1970 with a view to shedding light on the factors that determine the success or failure of fiscal adjustment. Compared to the existing literature on successful fiscal consolidations we add a number of new dimensions. Three deserve particular attention. Firstly, we explore a broader set of potential ingredients of the recipe for success. In addition to the composition of adjustment, which has extensively been examined in the literature, we consider further elements such as the quality and strength of fiscal governance and the implementation of structural reforms. Secondly, our analysis seeks to differentiate between at least two different types of consolidation episodes, one in which a relatively big fiscal correction is implemented in a short period of time, dubbed 'cold shower' consolidation, as compared to more gradual episodes of adjustment. Thirdly, we check whether the 'recipe for success' changed over time. Our analysis broadly confirms the results established in the literature for what concerns (i) the conditions triggering a consolidation episode and (ii) the composition of adjustment, with minor but important qualifications related to the role played by government wages. In addition it provides evidence that well-designed fiscal governance as well as structural reforms improve the odds of both starting a consolidation episode and achieving a lasting fiscal correction. Our analysis also shows that the composition of successful and unsuccessful consolidation has become more similar over time and that other discriminating factors such as fiscal governance and structural reforms turn out to make an increasing difference for success.Fiscal consolidations, fiscal rules, budgetary procedures, structural reforms

Jovian Early Bombardment: planetesimal erosion in the inner asteroid belt

The asteroid belt is an open window on the history of the Solar System, as it preserves records of both its formation process and its secular evolution. The progenitors of the present-day asteroids formed in the Solar Nebula almost contemporary to the giant planets. The actual process producing the first generation of asteroids is uncertain, strongly depending on the physical characteristics of the Solar Nebula, and the different scenarios produce very diverse initial size-frequency distributions. In this work we investigate the implications of the formation of Jupiter, plausibly the first giant planet to form, on the evolution of the primordial asteroid belt. The formation of Jupiter triggered a short but intense period of primordial bombardment, previously unaccounted for, which caused an early phase of enhanced collisional evolution in the asteroid belt. Our results indicate that this Jovian Early Bombardment caused the erosion or the disruption of bodies smaller than a threshold size, which strongly depends on the size-frequency distribution of the primordial planetesimals. If the asteroid belt was dominated by planetesimals less than 100 km in diameter, the primordial bombardment would have caused the erosion of bodies smaller than 200 km in diameter. If the asteroid belt was instead dominated by larger planetesimals, the bombardment would have resulted in the destruction of bodies as big as 500 km.Comment: 36 pages, 2 figures, 5 tables; accepted for publication on The Astrophysical Journa