On simple concrete giffen utility functions : old and new results

The authors present a theoretical review of the literature on simple concrete continuous utility functions for Giffen and inferior goods within the context of the utility maximisation problem under a budget restriction and provide new functional forms. The article is organised around the specific properties such utility functions have. These properties include increasingness, quasi-concavity, and the applicability of Gossen's Second Law

Linking of Repeated Games. When Does It Lead to More Cooperation and Pareto Improvements?

Linking of repeated games and exchange of concessions in fields of relative strength may lead to more cooperation and to Pareto improvements relative to the situation where each game is played separately. In this paper we formalize these statements, provide some general results concerning the conditions for more cooperation and Pareto improvements to materialize or not and analyze the relation between both. Special attention is paid to the role of asymmetries.Environmental Policy, Linking, Folk Theorem, Tensor Game, Prsioners' Dilemma, Full Cooperation, Pareto Efficiency, Minkowski Sum, Vector Maximum, Convex Analysis

Quantitative representation of reactivity, selectivity and site activation concepts in organic chemistry

Indexación: ScieloReactivity, selectivity and site activation are classical concepts in chemistry which are amenable to quantitative representation, in terms of static global, local and non local density response functions. The use of these electronic indexes describing chemical interconversion is developed in this work along the perspective of the pioneering work conducted in Chile by the late Professor Fernando Zuloaga, to whom this article is dedicated in memoriam. While global responses, represented as derivatives of the electronic energy with respect to the total number of electrons quantitatively describe the propensity of a system to interconvert into another chemical species (chemical reactivity), the local counterparts assesses well those regions in the molecule where the reactivity pattern dictated by the global quantities is developed (selectivity). Site activation /deactivation may in turn be described by the variations in the local or regional patterns of reactivity, that may be induced by solvent effects or chemical substitution. These concepts are illustrated for a series of chemical reactions in Organic Chemistry, including electrocyclic processes, cycloadditions and electrophilic addition reactions. Some relationships between quantitative scales of reactivity and reaction mechanisms are discussed.http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-97072004000100010&lang=p

Uniqueness of Coalitional Equilibria

We provide an existence and a uniqueness result for coalitional equilibria of a game in strategic form. Both results are illustrated for a public good game and a homogeneous Cournot-oligopoly game.Existence and uniqueness of coalitional equilibrium, Game in strategic form

Cournot equilibrium uniqueness via demi-concavity

AbstractA family of oligopolies that possess a unique equilibrium was identified in the second authors doctoral dissertation. For such a family, it is therein specified a class of functions-economically related to the price function of a Cournot oligopoly – that satisfy a particular type of quasi-concavity. The first part of the present article (i) conceptualizes that type of quasi-concavity by introducing the notion of demi-concavity, (ii) considers two possible variants and (iii) provides some calculus properties. The second part, by relying on the results on demi-concavity, proves a Cournot equilibrium uniqueness theorem which is new for the journal literature and subsumes various results thereof. A third part shows an example that illustrates the novelty of the result

An evaluation study for improving gap flow simulations in coastal areas on Portugal

Winds inferred by Synthetic Aperture Radar (SAR) satellites are a very important source of spatial wind field behavior along coastal areas particularly on small coastal areas that are temporary affected by strong flow disturbances mainly driven from land to the ocean. Gap flow circulations, among others, are an example of such wind phenomena disturbances which are not yet described by regional atmospheric models nor by CFD modeling. Such situations could compromise both offshore wind resource and park deployment studies on places affected by the presence of these phenomena types. A possible way to overcome this situation is the usage of SAR images assimilated into regional atmospheric models using certain type of assimilation techniques. In this work, a real case occurred in a coastal area in Portugal will be taken into account. A strong gap flow occurred during the beginning of the night 9 December 2010 was captured by a SAR image which was assimilated into the model. Some validation meteorological stations were used for validation purposes taken into account scenarios performed with and without wind SAR assimilation. Spatial results lead to the conclusion that the assimilation of SAR images improves the wind pattern results which reflects how SAR assimilation into the mesoscale models are important for simulating the coastal wind flow patterns

On the uniqueness of Cournot equilibrium in case of concave integrated price flexibility

We consider a class of homogeneous Cournot oligopolies with concave integrated price flexibility and convex cost functions. We provide new results about the semi-uniqueness and uniqueness of (Cournot) equilibria for the oligopolies that satisfy these conditions. The condition of concave integrated price flexibility is implied by (but does not imply) the log-concavity of a continuous decreasing price function. So, our results generalize previous results for decreasing log-concave price functions and convex cost functions. We also discuss the particular type of quasi-concavity that characterizes the conditional revenue and profit functions of the firms in these oligopolies and we point out an error of the literature on the equilibrium uniqueness in oligopolies with log-concave price functions. Finally, we explain how the condition of concave integrated price flexibility relates to other conditions on the price and aggregate revenue functions usually considered in the literature, e.g., their concavity

Securing land rights under rapid population growth: The feasibility of institutional land rights protection in Africa

The paper examines the claim that a virtuous cycle of more secure land rights, more land-saving investments, and denser populations requires the development of institutions that regulate competition over land. We construct a contest model that links the tenure-security-investment relationship to the efforts of land users to enhance land rights themselves and the role of institutional protection. We study the effect of population growth on a close-to-subsistence economy, including the possibility that it weakens institutional protection. We derive sufficient conditions for a positive effect on land investment, but also show that population growth can push the economy into a low-productivity trap

The two-stage game approach to coalition formation: Where we stand and ways to go

Coalition formation is often analysed in an almost non-cooperative way, as a two-stage game that consists of a first stage comprising membership actions and a second stage with physical actions, such as the provision of a public good. We formalised this widely used approach for the case where actions are simultaneous in each stage. Herein, we give special attention to the case of a symmetric physical game. Various theoretical results, in particular, for cartel games, are provided. As they are crucial, recent results on the uniqueness of coalitional equilibria of Cournot-like physical games are reconsidered. Various concrete examples are included. Finally, we discuss research strategies to obtain results about equilibrium coalition structures with abstract physical games in terms of qualitative properties of their primitives.</p