Limited memory and the essentiality of money

This paper investigates the relationship between memory and the essentiality ofmoney. We consider a random matching economy with a large finite population inwhich commitment is not possible and memory is limited in the sense that only afraction m E(0; 1) of the population has publicly observable histories. We show thatno matter how limited memory is, there exists a social norm that achieves the firstbest regardless of the population size. In other words, money can fail to be essentialirrespective of the amount of memory in the economy. This suggests that the emphasison limited memory as a fundamental friction for money to be essential deserves a deeperexamination.

Money versus memory

A well–established fact in monetary theory is that a key ingredient for the essentialityof money is its role as a form of memory. In this paper we study a notion ofmemory that includes information about an agent’s past actions and trading opportunitiesbut, in contrast to Kocherlakota (1998), does not include information aboutthe past actions and trading opportunities of an agent’s past partners. We first showthat the first–best can be achieved with memory even if it only includes informationabout an agent’s very recent past. Thus, money can fail to be essential even if memoryis minimal. We then establish, more interestingly, that if information about tradingopportunities is not part of an agent’s record, then money can be better than memory.This shows that the societal benefit of money lies not only on being a record of pastactions, but also on being a record of past trading opportunities, a fact that has beenoverlooked by the monetary literature.

Land suitability analysis to assess the potential of public open spaces for urban agriculture activities

Dissertation submitted in partial fulfilment of the requirements for the degree of Master of Science in Geospatial TechnologiesIn a world increasingly dominated by cities and an accelerated urban sprawl, urban agriculture emerges as an alternative for the continuous stock and food supply that urban population demands. This thesis aimed to identify and evaluate potential available areas in public locations for implementing urban agriculture practices within the urban perimeter of the city of Bogota in Colombia. The methodology was conducted using variables reflecting the physical, environmental and socioeconomic components of the area. Two approaches were implemented to evaluate a land suitability analysis for urban agriculture to alleviate urban poverty by increasing food security and nutrition in the study area. The first approach was based on expert knowledge combining GIS with multicriteria decision making analysis (MCDM) using analytical hierarchical process (AHP) method, estimating that 21% of the study area presents highly suitability conditions for implementing urban agriculture activities. The second approach was developed using supervised machine learning algorithms for classification models based on historical data of the current sites, where urban agriculture activities were being implemented in the city, showing that 18% of the study area is in high suitability conditions for the implementation of urban agriculture activities. Both approaches indicated that the areas of excellent suitability are located in the South and Southwestern parts of the study area, emphasizing its congruence with the areas with the lowest socioeconomic levels in the city. It was found that approximately 2% of the study area has available spaces in public locations with a significant potential for urban agriculture practices. Three projected scenarios were simulated where 10%, 30% and in the most utopic case 50% of these spaces would be used for urban agriculture activities and the vegetable productivity in tons of five of the most popular crops grown was estimated

Monetary equilibrium with decentralized trade and learning

This paper analyzes the stability of monetary regimes in an economy where fiat money isendogenously created by the government, information about its value is imperfect, and learningis decentralized. We show that monetary stability depends crucially on the speed of informationtransmission in the economy. Our model generates a dynamic on the acceptability of fiat moneythat resembles historical accounts of the rise and eventual collapse of overissued paper money.It also provides an explanation of the fact that, despite its obvious advantages, the widespreaduse of fiat money is only a recent development.

Ferroelectric properties of Bi0.5(Na0.8K0.2)0.5TiO3 ceramics

Different processing conditions and the effect of secondary phases on ferroelectric properties of Bi0.5(Na0.8K0.2)0.5TiO3 (BNKT) are studied. Ceramic powders are prepared by solid state reaction and different sintering temperatures (temperatures between 1075 and 1150ºC) are analyzed. Finally, samples are characterized by X-ray diffraction, Raman microspectroscopy, Scanning Electron Microscopy, impedance spectroscopy, and density measurements. Through XRD patterns, the perovskite structure is stabilized; together with small peaks corresponding to a secondary phase associated with K2-xNaxTi6O13 phase. Moreover, the content of the secondary phase, d33 piezoelectric constant and dielectric properties increase with sintering temperature.Fil: Camargo, Javier Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Ramajo, Leandro Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Rubio Marcos, Fernando. Instituto de Ceramica y Vidrio de Madrid; EspañaFil: Castro, Miriam Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

Diversification as a Form of Risk Management in Agriculture

The objective of this study is to show the importance of diversification in the risk management process. The study areas are: Mato Grosso, with large properties, and Rio Grande do Sul with small. The developed activities are annual cultures and cattle for slaughter. The hypotheses of the work are: a) rural producers diversify their activities using modern techniques. b) Diversification has been efficient in the producers' risks reduction. c) Producers tend be as effective as possible, though they differ in the rates of risk aversion. The MOTAD and E-V models were used.Farm Management,

Geoprossening tools applied in the analysis of land use evolution in the municipality of Rosana, SP, from 1984 and 2007

Este estudio tuvo como objetivo evaluar la evolución del uso del suelo en la ciudad de Rosana, São Paulo, entre 1984 y 2007, utilizando las técnicas de geoprocesamiento. Rosana está situado en el extremo oeste de São Paulo en la frontera con Mato Grosso do Sul a norte y Paraná a sur, siendo que en la frontera con Mato Grosso do Sul está el río Paraná y en frontera con Paraná, el rio Paranapanema. Con los resultados de las análisis se identificó la reducción de la cubierta forestal en lo municipio, la implantación de de nuevos cultivos y la reducción de grandes áreas de cultivo anteriormente utilizadas, provocados por el llenado de los lagos e hidroeléctricas de Rosana y Ingeniero Sérgio Motta (Porto Primavera).This study aimed to evaluate the evolution of land use in the city of Rosana-SP, between the years 1984 and 2007, using geoprocessing techniques. Rosana is located in the extreme west of São Paulo state, bordering the state of Mato Grosso do Sul in North and Parana in South, and, on the border with the state of Mato Grosso do Sul is the Parana River and the border with Parana, the Paranapanema River. The results of the analysis identified the reduction of forest cover in the municipality, the new crop area and a reduction in large areas formerly arable, removed by filling the lakes of the Rosana Hydroelectric and Engineer Sérgio Motta (Porto Primavera).O presente trabalho teve como objetivo avaliar a evolução do uso da terra do município de Rosana-SP, entre os anos de 1984 e 2007, utilizando técnicas de geoprocessamento. Rosana está localizada no extremo oeste do Estado de São Paulo, fazendo divisa com o Mato Grosso do Sul ao norte e Paraná ao sul, sendo que na divisa com o Estado do Mato Grosso do Sul encontra-se o rio Paraná e na divisa com o Paraná, o rio Paranapanema. O resultado das análises permitiu identificar a diminuição da cobertura florestal do município, a implantação de novas culturas e a redução de grandes áreas anteriormente agricultáveis, suprimidas com o enchimento dos lagos das Usinas Hidrelétricas de Rosana e Engenheiro Sérgio Motta (Porto Primavera)

As missões orientais do Uruguai: do Tratado de Madri ao Tratado de Santo Ildefonso

O período posterior à fundação de Colônia do Sacramento, até a assinatura do Tratado de Santo Ildefonso, na região platina, teve como característica geopolítica principal um grande esforço de ocupação do imenso território da margem esquerda do rio Uruguai. Obviamente, esse esforço se concentrou em áreas consideradas estratégicas, nos litorais fluviais e marítimos da região, com raras exceções. No caso português, a região de Laguna, as barras dos rios principais, como o Mampituba, o Tramandaí e o Rio Grande de São Pedro (Canal de São Gonçalo). No caso espanhol, os litorais internos dos campos orientales, nos rios Uruguai e da Prata e no litoral atlântico, até Maldonado. (Párrafo extraído del texto a modo de resumen)Aula "B": Perspectivas históricas de las Relaciones Internacionales.Instituto de Relaciones Internacionales (IRI

As missões orientais do Uruguai: do Tratado de Madri ao Tratado de Santo Ildefonso

O período posterior à fundação de Colônia do Sacramento, até a assinatura do Tratado de Santo Ildefonso, na região platina, teve como característica geopolítica principal um grande esforço de ocupação do imenso território da margem esquerda do rio Uruguai. Obviamente, esse esforço se concentrou em áreas consideradas estratégicas, nos litorais fluviais e marítimos da região, com raras exceções. No caso português, a região de Laguna, as barras dos rios principais, como o Mampituba, o Tramandaí e o Rio Grande de São Pedro (Canal de São Gonçalo). No caso espanhol, os litorais internos dos campos orientales, nos rios Uruguai e da Prata e no litoral atlântico, até Maldonado. (Párrafo extraído del texto a modo de resumen)Aula "B": Perspectivas históricas de las Relaciones Internacionales.Instituto de Relaciones Internacionales (IRI

As missões orientais do Uruguai: do Tratado de Madri ao Tratado de Santo Ildefonso

O período posterior à fundação de Colônia do Sacramento, até a assinatura do Tratado de Santo Ildefonso, na região platina, teve como característica geopolítica principal um grande esforço de ocupação do imenso território da margem esquerda do rio Uruguai. Obviamente, esse esforço se concentrou em áreas consideradas estratégicas, nos litorais fluviais e marítimos da região, com raras exceções. No caso português, a região de Laguna, as barras dos rios principais, como o Mampituba, o Tramandaí e o Rio Grande de São Pedro (Canal de São Gonçalo). No caso espanhol, os litorais internos dos campos orientales, nos rios Uruguai e da Prata e no litoral atlântico, até Maldonado. (Párrafo extraído del texto a modo de resumen)Aula "B": Perspectivas históricas de las Relaciones Internacionales.Instituto de Relaciones Internacionales (IRI