Money in Consumption Economies

Three sequential models of consumption economies are considered, where consumers´only endowment is money. The existence and unicity of temporary equilibria, the neutrality of money and the validity of quantity theory are investigated. In the first two models "money" is persihable; in the second one lending between consumers is possible. In the third model money is an asset and can be created through bank loans.

A Frictionless Economy With Subotimizing Agents

The existence of short-term monetary equilibrium in a frictionless economy with suboptimal agents is proved for any (reasonable) given interest rate. Separability ideas (as defined in Decision Theory) are applied. Two financial markets are in operation: for bank contracts (deposits and credits) and for shares.

Who Learns Better Bayesian Network Structures: Accuracy and Speed of Structure Learning Algorithms

Three classes of algorithms to learn the structure of Bayesian networks from data are common in the literature: constraint-based algorithms, which use conditional independence tests to learn the dependence structure of the data; score-based algorithms, which use goodness-of-fit scores as objective functions to maximise; and hybrid algorithms that combine both approaches. Constraint-based and score-based algorithms have been shown to learn the same structures when conditional independence and goodness of fit are both assessed using entropy and the topological ordering of the network is known (Cowell, 2001). In this paper, we investigate how these three classes of algorithms perform outside the assumptions above in terms of speed and accuracy of network reconstruction for both discrete and Gaussian Bayesian networks. We approach this question by recognising that structure learning is defined by the combination of a statistical criterion and an algorithm that determines how the criterion is applied to the data. Removing the confounding effect of different choices for the statistical criterion, we find using both simulated and real-world complex data that constraint-based algorithms are often less accurate than score-based algorithms, but are seldom faster (even at large sample sizes); and that hybrid algorithms are neither faster nor more accurate than constraint-based algorithms. This suggests that commonly held beliefs on structure learning in the literature are strongly influenced by the choice of particular statistical criteria rather than just by the properties of the algorithms themselves.Comment: 27 pages, 8 figure

Majorization, Matrix Transformations and Electoral Systems

[EN] This working paper entitled "Majorization, Matrix Transformations and Electoral Systems" presents a result that can be applied to the comparison of closed list electoral systems, providing a unified proof of the standard hierarchy of these electoral systems according to whether they are more or less favourable to larger parties.[ES] Estudio sobre transformación de matrices cuyo resultado puede ser aplicado a la comparación de sistemas electorales (con listas cerradas), proporcionando una demostración unificada de la jerarquía estándar de estos sistemas electorales según sean más o menos favorables a los partidos mayores

On conditional probability and bayesian inference

Measurement theory has dealt with the applicability of the conditional probability formula to the updating of probability assignments when new information is incorporated. In this paper the original probability measure is taken as given, and an assumption on the relation between this probability and a possible conditional probability is imposed. Provided that the original probability is non-atomic, it is proved that there is one and only one transformed probability measure satisfying the assumption. Building on this result, we discuss the hypotheses underlying Bayesian inference. In the Bayesian parametric model, a joint probability distribution on the product of the sample space and the parameter space is assigned. As this probability distribution is shown to be non-atomic, we conclude that, apart from measure-theoretic representability hypotheses, the existence of this joint probability is the only nontechnical hypothesis underlying Bayesian parametric statistical inference

A case of misreckoning: the Catalonian election of 2012

Las elecciones anticipadas al Parlamento Catalán de 2012 tuvieron un resultado inesperado. Por una parte, el predicho incremento del voto de los partidos nacionalistas (catalanes), tomados conjuntamente, no tuvo lugar. Por otra parte, en lo concerniente a las preferencias sobre la cuestión del nacionalismo hubo un desplazamiento hacia posiciones más militantes, a ambos lados del espectro. Como efecto de ambas componentes, la gobernante coalición CiU que había convocado las elecciones anticipadas sufrió una severa decepción. Las encuestas y las expectativas transmitidas por los medios de comunicación fallaron manifiestamente. En este artículo investigamos la dinámica entre las elecciones de 2010 y 2012, utilizando un procedimiento estadístico indirecto. La lengua resulta ser un factor clave. El hecho de que el apoyo a los partidos nacionalistas haya permanecido constante entre 2010 y 2012 es consecuencia de que este apoyo ha crecido entre los catalanohablantes y disminuido entre los castellanohablantes. Las dos organizaciones políticas que han dominado la política catalana, CiU (centro-derecha) y PSC (centro-izquierda), afrontan retos a sus papeles centrales. The 2012 snap election for the Catalan Parliament had a rather unexpected result. On the one hand, the predicted increase of the (Catalan) nationalist parties (taken together) did not take place. On the other hand, in the nationalist preferences dimension there was a shift towards more militant positions on both sides of the spectrum. All in all, the (Catalan) nationalist coalition in government calling the snap election suffered a harsh disappointment. Opinion polls and expectations conveyed by the media failed glaringly. In this paper we investigate the dynamic between the 2010 and 2012 elections, using an indirect statistical procedure. Language turns out to be a key factor. The fact that the support of nationalist parties has remained constant between 2010 and 2012 results from this support increasing among Catalan speakers and decreasing among Spanish speakers. The two political organizations that have dominated Catalan politics, CiU (centre-right) and PSC (centre-left), face challenges to their pivotal roles

Preference intensity without cardinality

La intensidad de preferencia es un concepto relevante, más general que el de preferencia cardinalmente representable, y se introduce una definición axiomática acorde. Se aplican los espacios uniformes como instrumento para estudiar la intensidad de preferencia. Se considera así la "unicidad" y la existencia de representación cardinal. Preference intensity is a relevant concept, more general than cardinal representable preference, and an according axiomatic definition is introduced. Uniform spaces are applied as a tool to study preference intensity. "Uniqueness" and the existence of cardinal representation are thus considered

Programa 21 e Educación Ambiental: raíces da Axenda 21 Escolar

O programa ou Axenda 21 nace no Cumio da Terra (1992) como un plano que marca as directrices para as políticas e estratexias que se levan a cabo no século XXI encamiñadas cara un desenvolvemento sostible. Dous anos máis tarde moitas cidades europeas subscriben a Carta de Aalborg para desenvolver a denominada Axenda 21 Local. Paralelamente, a educación ambiental - nacida a mediados de século pasado - atópase nun momento complexo, coa propia aparición do termo desenvolvemento sustentable e certo pesimismo sobre os resultados concretos da súa traxectoria. No ámbito da educación formal, a sinerxía producida polo desenvolvemento da Axenda 21 Local unido ao interese da escola tanto por mellorar a calidade ambiental e educativa dos centros escolares coma por intervir e participar no ámbito próximo (barrio, distrito, municipio, ...) xera a Axenda 21 Escolar. Este programa estase a desenvolver ao longo do planeta seguindo diferentes modelos e cun substrato común: traballar por e para o centro escolar e o municipio. Ten unhas grandes potencialidades que o converten nunha alternativa válida para afrontarmos os retos da educación do século XXI e da nova educación ambiental

Triquinas, cerdos y salud pública veterinaria: la inclusión del mundo microscópico en la base científica de la inspección cárnica (Barcelona, 1870s)

Ganador XLVI Premio Fundación Uriach de "Historia de la MedicinaDurante la segunda mitad del siglo XIX las autoridades españolas comenzaron a desarrollar programas específicos sobre la seguridad de algunos alimentos destinados al consumo humano. Este trabajo analiza las claves que propiciaron la inclusión del veterinario como parte integrante de la estructura administrativa encargada de salvaguardar la salud pública. Entre los aspectos tratados, se ha profundizado en las relaciones entre las medicinas humana y animal en un momento en que la alarma social originada por algunas zoonosis contribuyó a configurar la noción de una salud pública veterinaria. La aparición de una enfermedad en el ganado porcino transmisible por el consumo de carne parasitada conformó un escenario favorable para equiparar inspección veterinaria con garantía sanitaria. Los brotes de triquinosis que salpicaron la geografía española en la década de 1870 evidenciaron la existencia de un «contagio animado» en una época prebacteriológica e impulsaron la introducción de mejoras en la inspección alimentaria. En este sentido, la indagación microscópica de los productos de origen porcino imprimió un impulso modernizador a la labor inspectora de los veterinarios, más centrada hasta entonces en vigilar las características organolépticas de carnes y pescados y en advertir fraudes. La introducción del microscopio contó con una aceptación generalizada y marcó una barrera entre las formas válidas e inválidas de realizar el reconocimiento de las carnes. Además, esa manera «tecnológica» de diagnosticar aproximaba la veterinaria a otras profesiones sanitarias de mayor prestigio, al menos en el plano teórico. Entre otras cosas, la aceptación de la triquina como causa exógena de enfermedad contribuyó a que algunos médicos decimonónicos se familiarizasen con la doctrina explicativa del contagio de la mano de los veterinarios. A nivel social, el uso de este instrumento debería prevenir la transmisión al hombre de una enfermedad animal que estaba de actualidad. Y desde el punto de vista político, este proceso, analizado en el presente trabajo desde la óptica barcelonesa, nos deja entrever un contraste entre el afán modernizador de algunos veterinarios catalanes frente a lo que ocurría en otras partes de España.During the second half of the 19th century, Spanish authorities began developing specific programs on the safety of certain foods intended for human consumption. This paper analyses the key features that gave rise to the inclusion of the veterinarian in the administrative structure responsible for safeguarding public health. Among the aspects covered, special focus is put on the relationship between human and animal medicine at a time when growing public alarm in relation to certain zoonoses contributed to shaping the notion of veterinary public health. The appearance of a disease in pigs that was transmissible through the consumption of parasitized meat set the scene for veterinary inspection to be associated with the protection of public health. The outbreaks of trichinosis all over Spain in the 1870's proved the existence of contagium animatum in a pre-bacteriology era, and this led to the introduction of improvements in food inspection. In this sense, microscopic examination of pork products encouraged the modernization of inspection tasks undertaken by veterinarians, which had previously focused on the organoleptic evaluation of meat and fish and on unveiling fraud. The introduction of microscopes was widely accepted and established a watershed between acceptable and unacceptable methods of carrying out the examination of meat. Furthermore, this "technological" method of diagnosis brought veterinary medicine closer to other more prestigious health professions, at least in theory. Among other aspects, the acceptance of trichinae as an exogenous cause of disease contributed to 19th century doctors learning about the idea of pathogenic microorganisms from veterinarians. At a social level, the use of the microscope was seen as a way of preventing the transmission to people of an animal disease that was very much in the public eye at the time. From the political point of view, the process -analysed in this paper from the perspective of veterinarians in Barcelona- allows a glimpse of the contrast between the desire of some Catalan veterinarians to modernize their profession and what was happening in others parts of Spain

Science, progress, and livestock engineering in twentieth century veterinary medicine in Spain

At the beginning of the twentieth century, Spanish veterinarians were faced with reforms that redefined their work. One objective was to promote the transformation of veterinary science in Spanish life, by emphasizing its scientific aspect as evidence of its modernization. Just one formula was applied to support professional interests in the reform and it implied a shift toward two disciplines that enjoyed high social recognition, namely, engineering and medicine. This sociological redefinition focused on the campaign launched by the veterinary press to change the name of the profession