RURAL CREDIT RATIONING AND NATIONAL DEVELOPMENT BANKS IN DEVELOPING COUNTRIES

A common problem in agricultural credit markets in developing countries is the coexistence of a competitive market equilibrium interest rate and credit rationing. The literature typically explains the existence of credit rationing in competitive credit markets using adverse selection and moral hazard. Unfortunately these analyses are not consistent with the empirical reality that developing countries deal with in terms of subsidized credit, especially in the agricultural sector. This paper presents an alternative explanation for credit rationing in the agricultural sector in developing countries based on the fact that the requested loans are usually for small amounts, with many farmers making applications. As a result, the costs of operation increase with the number of loans given, so that inefficiencies in credit allocation occur when national development banks are present. It is shown that credit rationing can be reduced if shutting-down the national development bank is a feasible policy. Two other cases show that a national development bank is welfare-improving if an incentive compatible contract is used.Financial Economics,

Desarrollo de modelos de predicción de la generación de energía eólica y solar para la optimización de centros de datos en un entorno de Smart Grid

En la actualidad vivimos un continuo incremento de la demanda eléctrica, por otro lado, también se dedican más recursos renovables a abastecer dicho consumo debido a que, a diferencia de los combustibles fósiles, las fuentes renovables no contaminan ni favorecen el calentamiento global. Esto, junto al continuo abaratamiento de la infraestructura de una red de autoconsumo, resulta en una posible solución al problema de la demanda energética global: provisionar un sistema, íntegra o parcialmente, con una red de autoconsumo de energías renovables. Una parte importante de este consumo es debida a los Centros de Procesamiento de Datos. Estos centros tienen como objetivo procesar toda la información de una organización. Dichos espacios procesan datos ininterrumpidamente durante periodos de tiempo muy extensos lo que implica un consumo prolongado en el tiempo. Este sistema puede ser abastecido si se combinan satisfactoriamente varios elementos: La red eléctrica convencional, una infraestructura de autoconsumo de energías renovables y un conjunto de baterías. La complejidad radica en saber cuándo y cómo usar cada uno de estos elementos. (i.e. En un periodo de máxima producción solar, no tendría sentido consumir directamente de la red eléctrica). El elemento que añade mayor variedad al cuándo y cómo es la producción de energías renovables. Si tratamos con el sol, no se sabe con certeza cuándo se nublará, o tratando con el viento, cuánto y en qué dirección soplará. Por esto centraremos el trabajo en dicha complicación: Predecir la energía producida. Para ello estudiaremos múltiples modelos de predicción enfocados a la predicción energética, no a la meteorológica, y evaluaremos los resultados obtenidos. Para ello tomaremos valores meteorológicos extraídos de una estación para, con un modelo detallado de la planta solar o un parque eólico, obtener valores energéticos lo más realistas posibles y aplicar los modelos predictivos a éstos con el fin de obtener y contrastar las predicciones. Con los resultados obtenidos se espera poder evaluar la capacidad y calidad actual de la técnica y en consecuencia, su viabilidad

Essays in monetary policy conduction and its effectiveness: monetary policy rules, probability forecasting, central bank accountability, and the sacrifice ratio

Monetary policy has been given either too many positive attributes or, in contrast, only economy-disturbing features. Central banks must take into account a wide variety of factors to achieve a proper characterization of modern economies for the optimal implementation of monetary policy. Such is the case of central bank accountability and monetary policy effectiveness. The objective of this dissertation is to examine these two concerns relevant to the current macroeconomic debate. The analyses are carried out using an innovative set of tools to extract presumably important information from historical data of selected macroeconomic indicators. This dissertation consists of three essays. The first essay explores the causality between the elements of the "celebrated" Taylor rule, using a Structural Vector Autoregression approach on US data. Directed acyclical graph techniques and Bayesian search models are used to identify the contemporaneous causal structure in the construction of impulse-response functions. Further analysis is performed by evaluating the implications of performing standard innovation-accounting procedures, derived from a Structural Vector Autoregression on interest rates, inflation, and unemployment. This is examined whenever a causal structure is imposed vs. when it is observed. We find that the interest rate causes inflation and unemployment. This suggests that the Fed has not followed a Taylor rule in any of the two periods under study. This result differs significantly to the case when the causal structure is imposed. The second essay presents an incentive-compatible approach based on proper scoring rules to evaluate density forecasts in order to reduce the central banks' accountability problem. Our results indicate that the surveyed forecasters have done a "better" job than the Monetary Policy Committee (MPC). The third essay analyzes the causal structure of the factors that are presumed to influence the effectiveness of monetary policy, represented by the sacrifice ratio. Directed acyclical graph methods are used to identify the causal flow between such determinants and the sacrifice ratio. We find evidence that, while wage rigidities and central bank independence are the two major determinants of the sacrifice ratio, the degree of openness has no direct effect on the sacrifice ratio

Germinación diferencial asociada con viviparidad facultativa en Stenocereus thurberi (Cactaceae): correlaciones climáticas en poblaciones marginales de Sinaloa, México

Background and Aims: Precocious (viviparous) seed germination in fruits of Stenocereus thurberi has been correlated with higher germination rate of the remaining seeds. This study compares the germination of five populations from Sinaloa, Mexico, to determine: 1) whether there is a pattern associated with precocious seed germination and, 2) how much the viviparous phenomenon accounts for germination compared to variation between fruits, individuals and populations of the cactus.Methods: The incidence of vivipary was recorded in 194 plants, and seeds were separated into four putative sources of variance: populations, reproductive categories (VV: viviparous, NV: non-viviparous), individuals within categories and fruits within individuals. The seed germination response in percentage (PGF), mean time (TMG), rate (VG), and synchrony of germination (SG) was evaluated under a randomized complete blocks scheme with three replicates, in experimental units of 25 seeds. Data were analyzed with hierarchical ANOVAs for a linear mixed model.Key results: Reproductive categories accounted for 5-11% of variance and showed significant differences in favor of viviparous phenotypes, with PGF of 35 vs 19% and 91 vs 72%, VG of 1.5 vs 0.5 and 7.9 vs 5.4 seeds/day, and SG of 0.3 vs 0.1, 0.7 vs 0.5 and 0.8 vs 0.6. Buenavista and Tosalibampo populations showed higher percentage, rate and synchrony of germination than the other populations (P<0.05, Student t-test).Conclusions: There is a seed germination pattern associated to vivipary in S. thurberi. The variance accounted by this condition depends on the environment in which seed maturation and germination occur. The seeds from viviparous phenotypes showed higher germination vigor than seeds from non-viviparous plants, revealing potential for seedling recruitment and population growth under drought and salinity stress.Antecedentes y Objetivos: La germinación precoz (vivípara) de semillas en frutos de Stenocereus thurberi se ha correlacionado con mayor velocidad de germinación de las semillas remanentes. Esta investigación compara la germinación de cinco poblaciones de Sinaloa, México, para determinar: 1) si existe un patrón asociado con la germinación precoz de las semillas y 2) cuánto contribuye el fenómeno vivíparo a la germinación, dada la variación entre frutos, individuos y poblaciones de esta especie.Métodos: Se revisó el nivel de viviparidad de 194 plantas y se separaron las semillas en cuatro probables fuentes de varianza: poblaciones, categorías reproductivas (VV: vivíparas y NV: no vivíparas), plantas dentro de categorías y frutos dentro de plantas. Las respuestas de germinación final (PGF), tiempo medio (TMG), velocidad (VG) y sincronía de germinación (SG) se evaluaron en bloques al azar con tres repeticiones, en unidades experimentales de 25 semillas. Los datos se analizaron con ANOVA’s jerárquicos bajo un modelo lineal mixto.Resultados clave: Las categorías reproductivas explicaron 5-11% de la varianza y mostraron diferencias significativas a favor de las vivíparas, con PGF de 35 vs 19% y 91 vs 72%, VG de 1.5 vs 0.5 y 7.9 vs 5.4 semillas/día, y SG de 0.3 vs 0.1, 0.7 vs 0.5 y 0.8 vs 0.6. Las poblaciones de Buenavista y Tosalibampo tuvieron mayor porcentaje, velocidad y sincronía de germinación (prueba t de Student, P<0.05) que las otras poblaciones.Conclusiones: Existe un patrón de germinación asociado con viviparidad en S. thurberi. La varianza asociada con esta condición depende del ambiente de maduración y germinación de las semillas. Los fenotipos vivíparos germinaron con mayor vigor que los no vivíparos, mostrando potencial para apoyar la incorporación de individuos y el crecimiento de la población en condiciones de estrés hídrico y salino

Chiapas : entre el autoritarismo y la transición democrática, desde Acteal hasta el diálogo EZLN y sociedad civil

Obra cuya intención es dar cuenta de los diversos actores sociales involucrados en el conflicto de Chiapas, a nivel político, económico y sociocultural. El texto recupera un taller de análisis de coyuntura sobre el tema, realizado en agosto de 1998.ITESO, A.C

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

EDUCACIÓN AMBIENTAL Y SOCIEDAD. SABERES LOCALES PARA EL DESARROLLO Y LA SUSTENTABILIDAD

Este texto contribuye al análisis científico de varias áreas del conocimiento como la filosofía social, la patología, la educación para el cuidado del medio ambiente y la sustentabilidad que inciden en diversas unidades de aprendizaje de la Licenciatura en Educación para la Salud y de la Maestría en Sociología de la SaludLas comunidades indígenas de la sierra norte de Oaxaca México, habitan un territorio extenso de biodiversidad. Sin que sea una área protegida y sustentable, la propia naturaleza de la región ofrece a sus visitantes la riqueza de la vegetación caracterizada por sus especies endémicas que componen un paisaje de suma belleza

Multidimensional signals and analytic flexibility: Estimating degrees of freedom in human speech analyses

Recent empirical studies have highlighted the large degree of analytic flexibility in data analysis which can lead to substantially different conclusions based on the same data set. Thus, researchers have expressed their concerns that these researcher degrees of freedom might facilitate bias and can lead to claims that do not stand the test of time. Even greater flexibility is to be expected in fields in which the primary data lend themselves to a variety of possible operationalizations. The multidimensional, temporally extended nature of speech constitutes an ideal testing ground for assessing the variability in analytic approaches, which derives not only from aspects of statistical modeling, but also from decisions regarding the quantification of the measured behavior. In the present study, we gave the same speech production data set to 46 teams of researchers and asked them to answer the same research question, resulting insubstantial variability in reported effect sizes and their interpretation. Using Bayesian meta-analytic tools, we further find little to no evidence that the observed variability can be explained by analysts’ prior beliefs, expertise or the perceived quality of their analyses. In light of this idiosyncratic variability, we recommend that researchers more transparently share details of their analysis, strengthen the link between theoretical construct and quantitative system and calibrate their (un)certainty in their conclusions

RURAL CREDIT RATIONING AND NATIONAL DEVELOPMENT BANKS IN DEVELOPING COUNTRIES

A common problem in agricultural credit markets in developing countries is the coexistence of a competitive market equilibrium interest rate and credit rationing. The literature typically explains the existence of credit rationing in competitive credit markets using adverse selection and moral hazard. Unfortunately these analyses are not consistent with the empirical reality that developing countries deal with in terms of subsidized credit, especially in the agricultural sector. This paper presents an alternative explanation for credit rationing in the agricultural sector in developing countries based on the fact that the requested loans are usually for small amounts, with many farmers making applications. As a result, the costs of operation increase with the number of loans given, so that inefficiencies in credit allocation occur when national development banks are present. It is shown that credit rationing can be reduced if shutting-down the national development bank is a feasible policy. Two other cases show that a national development bank is welfare-improving if an incentive compatible contract is used