Top Monotonicity: A Common Root for Single Peakedness, Single Crossing and the Median Voter Result

When the members of a voting body exhibit single peaked preferences, majority winners exist. Moreover, the median(s) of the preferred alternatives of voters is (are) indeed the majority (Condorcet) winner(s). This important result of Duncan Black (1958) has been crucial in the development of public economics and political economy, even if it only provides a sufficient condition. Yet, there are many examples in the literature of environments where voting equilibria exist and alternative versions of the median voter results are satisfied while single peakedness does not hold. Some of them correspond to instances where other relevant conditions, apparently not connected with single eakedness, are satisfied. For example preferences may satisfy the single-crossing property (Mirrlees, 1971, Gans and Smart, 1996, and Milgrom and Shannon, 1994), intermediateness (Grandmont, 1978) or order restriction (Rothstein, 1990). Still other interesting cases of existence of voting equilibria do not fall in any of these categories. We present a new and weak domain restriction which encompasses all the above mentioned ones, llows for new cases, still guarantees the existence of Condorcet winners and preserves a version of the median voter result. We illustrate how this new condition, that we call top monotonicity, arises naturally in different economic contexts.Single peaked, single crossing and intermediate preferences, majority (Condorcet) winners

UNIFORM OUTPUT SUBSIDIES IN AN ECONOMIC UNION WITH FIRMS HETEROGENEITY

In this paper we show the importance of cost asymmetry and demand curvature in the effect of a uniform output subsidy policy in an economic union. We consider an economic union formed by two countries each with a single firm producing a homogeneous good. We find that when firms have different cost, the optimal level of the uniform subsidy can be negative if the demand is concave enough. The low cost firm expands its market share if the demand function is sufficiently convex whereas in the case of a concave demand function it is the higher cost firm which gains market share. This implies that a uniform output subsidy policy may cause a change in production e¢ciency. Finally, we consider how a divergence between private and social costs of public funds may a¤ect the desirability of such a subsidy policy.Uniform output subsidy policy, economic union, social welfare, cost differences

Single-dipped preferences

We characterize the set of all individual and group strategy-proof rules on the domain of all single-dipped preferences on a line. For rules defined on this domain, and on several of its subdomains, we explore the implications of these strategy-proofness requirements on the maximum size of the rules' range. We show that when all single-dipped preferences are admissible, the range must contain two alternatives at most. But this bound changes as we consider different subclasses of single-dipped preferences: we provide examples of subdomains admitting strategy-proof rules with larger ranges. We establish exact bounds on the maximal size of strategy-proof functions on each of these domains, and prove that the relationship between the sizes of the subdomains and those of the ranges of strategy-proof functions on them need not be monotonic. Our results exhibit a sharp contrast between the structure of strategy-proof rules defined on subdomains of single-dipped preferences and those defined on subsets of single-peaked ones.strategy-proof, group strategy-proof, binary range rules, single-dipped

Individual versus group strategy-proofness: when do they coincide?

A social choice function is group strategy-proof on a domain if no group of agents can manipulate its final outcome to their own benefit by declaring false preferences on that domain. Group strategy-proofness is a very attractive requirement of incentive compatibility. But in many cases it is hard or impossible to find nontrivial social choice functions satisfying even the weakest condition of individual strategy-proofness. However, there are a number of economically significant domains where interesting rules satisfying individual strategy-proofness can be defined, and for some of them, all these rules turn out to also satisfy the stronger requirement of group strategy-proofness. This is the case, for example, when preferences are single-peaked or single-dipped. In other cases, this equivalence does not hold. We provide sufficient conditions defining domains of preferences guaranteeing that individual and group strategy-proofness are equivalent for all rules defined on theStrategy-proofness, Group strategy-proofness, k-size strategy-proofness, Sequential inclusion, Single-peaked preferences, Single-dipped preferences, Separable preferences.

Two Necessary Conditions for Strategy-Proofness: on What Domains are they also Sufficient?

A social choice function may or may not satisfy a desirable property depending on its domain of definition. For the same reason, different conditions may be equivalent for functions defined on some domains, while different in other cases. Understanding the role of domains is therefore a crucial issue in mechanism design. We illustrate this point by analyzing the role of different conditions that are always related, but not always equivalent to strategy-proofness. We define two very natural conditions that are necessary for strategy-proofness: monotonicity and reshuffling invariance. We remark that they are not always sufficient. Then, we identify a domain condition, called intertwinedness, that ensures the equivalence between our two conditions and that of strategy-proofness. We prove that some important domains are intertwined: those of single-peaked preferences, both with public and private goods, and also those arising in simple models of house allocation. We prove that other necessary conditions for strategy-proofness also become equivalent to ours when applied to functions defined on intertwined domains, even if they are not equivalent in general. We also study the relationship between our domain restrictions and others that appear in the literature, proving that we are indeed introducing a novel proposal.strategy-proofness, reshuffling invariance, monotonicity, intertwined domains

Group strategy-proof social choice functions with binary ranges and arbitrary domains: characterization results

We define different concepts of group strategy-proofness for social choice functions. We discuss the connections between the defined concepts under different assumptions on their domains of definition. We characterize the social choice functions that satisfy each one of them and whose ranges consist of two alternatives, in terms of two types of basic properties.Social choice functions, Binary ranges, group strategy-proofness, xy-monotonicity, xy-based rules.

El "Libro I" de "Confisyon del Amante" de Juan de Cuenca, la traducción castellana de "Confessio Amantis" de John Gower (II)

En este artículo se presenta una edición de la segunda sección del libro I La Confesión del Amante, de Juan de Cuenca en la traducción castellana del siglo XV de John Gover. La primera parte ya se publicó en el volumen anterior del Anuario de Estudios Filológicos, vol. XIV, 1991, pp. 383-403.This article presents an edition of the second section of the First Book of Juan de Cuenca's Confisyon del Amante, the fifteenth-century Castilian translation of John Gower's Confessio Amantis. The first section was published in the previous volume of Anuario de Estudios Filológicos, vol. XIV, 1991, pp. 383-403

Output subsidies and quotas under uncertainty and firm heterogeneity

This paper studies the relative efficiency of two kinds of regulations, quantity restrictions (quotas) and output subsidies, in an imperfectly competitive market under the existence of two sources of uncertainty: uncertainty in both costs and prices. We find that when the two sources of uncertainty are independently distributed, the output subsidy instrument has comparative advantage over the quantity instrument. However, when we take into account the possibility of correlation between the random components and across firms marginal costs, we find that a positive (negative) correlation tends to favor the quantity (subsidy) instrument. Finally, we show that when the correlation is positive, it is possible to find situations in which the quantity instrument has comparative advantage over the subsidy instrument.Cost uncertainty, demand uncertainty, firm heterogeneity, output subsidy and quantity instruments

La traducción de "Confessio Amantis" de John Gower

La traducción de “La Confessio Amantis” de John Gower ha sido tema de estudio para algunos críticos, especialmente desde la publicación de la obra completa de John Gower, de G.C Macaulay (Oxford: Clarendon Press, 1901). Este artículo trata de algunos aspectos como fechas y circunstancias de la traducción que han sido erróneamente asumidos los últimos 200 años.The translation of John Gower's Confessio Amantis has been the subject of study for some critics, especially since G. C. Macaulay's publication of The Complete Works of John Gower (Oxford: Clarendon Press, 1901). This article deals with some aspects, such as the dates and circumstances of the translation, that have been wrongly assumed for the last 200 years

El prologo de “Confisyon del amante” de Juan de Cuenca, la traducción castellana de “Confessio amantis” de John Gower

"Confisyon del amante", ms. g-II-19 de la Real Biblioteca de El Escorial, es la versión del siglo XV en prosa castellana de la obra de John Gower "Confessio Amantis". Esta es la primera traducción al inglés de una obra literaria en una lengua extranjera. El "Prólogo" de "Confisyon del amante" es una unidad completa del texto castellano y muestra las mismas características básicas que se encuentran en el resto de la traducción. Esta edición del "Prólogo" es la transcripción del propio autor del manuscrito de El Escorial.Confisyon del amante, ms. g-ii-19 of the Royal Library of El Escorial, is the fifteenth- Century Castilian prose version of John Gower's Confessio Amantis. This is the first translation of an English literary work into a foreign language. The «Prologue» of Confisyon del amante is a complete unit of the Castilian text and shows the same basic characteristics to be found in the rest of the translation. This edition of the «Prologue» is the author's own transcription of the Escorial manuscript