The implementation of graphic organizers to teach reading comprehension skills to second graders of the sur oriental Boston Branch School

El propósito del siguiente proyecto fue seguir una secuencia didáctica y aplicar mapas mentales tal como un organizador gráfico como herramienta de entendimiento y al mismo tiempo mejorar las habilidades de lectura en el L2 con el fin de guiar los aprendices a localizar y clasificar información usando un mapa mental como un organizador gráfico para mejorar las habilidades de lectura

La recuperación de plusvalías urbanas en Bogotá: análisis contextual para el caso colombiano del enfoque de Martin Smolka respecto a la recuperación de plusvalías en Latinoamérica

Peer Reviewe

A Multi-Stage Almost Ideal Demand System: the case of beef demand in Colombia

The main objective in this paper is to obtain reliable long-term and short-term elasticities estimates of the beef demand in Colombia using quarterly data since 1998 until 2007. However, complexity on the decision process of consumption should be taken into account, since expenditure on a particular good is sequential. In the case of beef demand in Colom- bia, a Multi-Stage process is proposed based on an Almost Ideal Demand System (AIDS). The econometric novelty in this paper is to estimate si- multaneously all the stages by the Generalized Method of Moments to obtain a joint covariance matrix of parameters estimates in order to use the Delta Method for calculating the standard deviation of the long-term elasticities estimates. Additionally, this approach allows us to get elastic- ities estimates in each stage, but also, total elasticities which incorporates interaction between stages. On the other hand, the short-term dynamic is handled by a simultaneous estimation of the Error Correction version of the model; therefore, Monte Carlo simulation exercises are performed to analyse the impact on beef demand because of shocks at di erent levels of the decision making process of consumers. The results indicate that, although the total expenditure elasticity estimate of demand for beef is 1.78 in the long-term and the expenditure elasticity estimate within the meat group is 1.07, the total short-term expenditure elasticity is merely 0.03. The smaller short-term reaction of consumers is also evidenced on price shocks; while the total own price elasticity of beef is -0.24 in the short-term, the total and within meat group long-term elasticities are - 1.95 and -1.17, respectively.The main objective in this paper is to obtain reliable long-term and short-term elasticities estimates of the beef demand in Colombia using quarterly data since 1998 until 2007. However, complexity on the decision process of consumption should be taken into account, since expenditure on a particular good is sequential. In the case of beef demand in Colom- bia, a Multi-Stage process is proposed based on an Almost Ideal Demand System (AIDS). The econometric novelty in this paper is to estimate si- multaneously all the stages by the Generalized Method of Moments to obtain a joint covariance matrix of parameters estimates in order to use the Delta Method for calculating the standard deviation of the long-term elasticities estimates. Additionally, this approach allows us to get elastic- ities estimates in each stage, but also, total elasticities which incorporates interaction between stages. On the other hand, the short-term dynamic is handled by a simultaneous estimation of the Error Correction version of the model; therefore, Monte Carlo simulation exercises are performed to analyse the impact on beef demand because of shocks at di erent levels of the decision making process of consumers. The results indicate that, although the total expenditure elasticity estimate of demand for beef is 1.78 in the long-term and the expenditure elasticity estimate within the meat group is 1.07, the total short-term expenditure elasticity is merely 0.03. The smaller short-term reaction of consumers is also evidenced on price shocks; while the total own price elasticity of beef is -0.24 in the short-term, the total and within meat group long-term elasticities are - 1.95 and -1.17, respectively

Una función de producción agregada para la economía colombiana: características e interacción entre el trabajo calificado, el trabajo no calificado y el capital, 1994–2005.

En este artículo se enseñan los resultados de las diversas elasticidades del trabajo calificado, el trabajo no calificado y el capital que se obtienen asumiendo una función de producción agregada translogarítmica para la economía colombiana. En general se encuentra que el trabajo calificado ha ganado participación al interior del proceso productivo en detrimento del trabajo no calificado y el capital. En general, los factores productivos son bienes normales, pero el trabajo calificado es el que reacciona más fuertemente ante expansión en el producto. Por otra parte, el trabajo no calificado es el factor productivo que presenta el mayor valor absoluto de la elasticidad precio de la demanda. Finalmente, se evidencia una relación de complementariedad entre el trabajo calificado y los otros dos factores, pero se presenta una relación de sustitubilidad entre el capital y el trabajo no calificado. Este acontecimiento microeconómico, unido al abaratamiento del costo de uso del capital y el encarecimiento del trabajo no calificado explican el poco descenso que ha experimentado la tasa de desempleo en la economía colombiana, pese al buen desempeño macroeconómico reciente.This paper estimates the skilled labor, unskilled labor and capital elasticities when it is assumed a translogarithmic production function for the Colombian economic. It is found that the skilled labor remuneration has risen its participation while the other production factors remuneration have gotten down. In general, the production factors are normal goods, but the skilled labor is the factor that has more reaction to changes to the aggregate production. On the other hand, the unskilled labor is the factor that has the highest price elasticity to the demand in absolute value. Finally, it is found that there is a complementary relation between the skilled labor and the other factors, but there is a substitution relation between the unskilled labor and the capital. These microeconomic facts join to the lower capital cost and the higher unskilled labor price explain the small fall in the unemployment rate while the macroeconomic environment is good

Una Panorámica Sobre la Evolución de la Deuda Externa Colombiana: ¡Juegos Ponzi! ¿Hasta Cuándo?

En este artículo se analiza la evolución temporal de la deuda externa colombiana durante las últimas décadas enfatizando en sus dos grandes componentes: la deuda pública y la deuda privada. El análisis se realizará a partir del estudio de la relación de la deuda con la cuenta corriente. La investigación considerará el componente permanente de las series en cuestión y la senda temporal de dicho componente a través del tiempo. Además, se estiman las implicaciones del comportamiento de la deuda desde la perspectiva de un modelo estocástico para una pequeña economía abierta y la restricción presupuestaria que se impone a partir de la prohibición de juegos Ponzi. Luego se realizan algunas reflexiones sobre la sostenibilidad de la deuda externa. Deuda externa, Componente permanente. - See more at: http://www.bdigital.unal.edu.co/27231/#sthash.wbtJBXEB.dpu

Modelos de elección discreta: una aplicación a la demanda por cupos universitarios en Colombia.

En este artículo se realiza una caracterización cuantitativa de la demanda de cupos universitarios por parte de bachilleres egresados de ciudades intermedias. Esto se realiza a través de modelos de elección discreta. Específicamente se encuentra que el número de programas ofrecidos aumenta la probabilidad de selección de las universidades por parte de los bachilleres, mientras que el ranking universitario está inversamente relacionado con dicha probabilidad. Por otra parte, se encuentra que la posición socioeconómica, medida a través del estrato, es una variable bastante explicativa de la elección universitaria; específicamente, los bachilleres provenientes de estratos bajos y medios tienden a optar por universidades públicas, mientras que los bachilleres de estratos altos seleccionan universidades privadas.This article makes a quantitative characterization of high school graduates from intermediate cities and their demand for university places. Specifically speaking, the results show that the number of programs offered by universities increases the probability of choosing the latter,whereas university ranking has an inverse relationship with that probability. On the other hand, the socio-economic state of high school graduates measured by their “estrato” is a variable that explains their choice of university. Specifically, the students from low and middle estratos show a strong trend in terms of choosing public universities, whereas those from high estratos prefer private universities

Consequences of omitting relevant inputs on the quality of the data envelopment analysis under different input correlation structures

This paper establishes the consequences of a wrong specification on the quality of the data envelopment analysis. Specifically, the case of omitting a relevant variable in the input oriented problem is analyzed when there are different correlation structures between the inputs. It is established that the correlation matrix gives relevant information about the homogeneity of the decision making units and the intensity of inputs used in the production process. The methodology is based on a series of Monte Carlo simulations and the quality of the data envelopment analysis is measured as the difference between the true efficiency and the efficiency calculated. It is found that omitting relevant inputs causes inconsistency, and this problem is worse when there is a negative correlation structure.This paper establishes the consequences of a wrong specification on the quality of the data envelopment analysis. Specifically, the case of omitting a relevant variable in the input oriented problem is analyzed when there are different correlation structures between the inputs. It is established that the correlation matrix gives relevant information about the homogeneity of the decision making units and the intensity of inputs used in the production process. The methodology is based on a series of Monte Carlo simulations and the quality of the data envelopment analysis is measured as the difference between the true efficiency and the efficiency calculated. It is found that omitting relevant inputs causes inconsistency, and this problem is worse when there is a negative correlation structure

Limitantes de la interculturalidad en la Sierra Norte de Puebla, México

La sierra noroccidental de Puebla (México) ha pasado en los últimos años de estar en la vanguardia en cuanto a la promoción de las culturas originarias y de la interculturalidad entre estas y la modernidad, a un retroceso generalizado de dicho proceso. En este artículo se analiza esta regresión en las organizaciones que estaban sirviendo de modelo de interculturalidad. Al relacionar las diversas dinámicas específicas observadas en cada organización aparece, por un lado, una rigidez en las instituciones modernas que limita la interculturalidad, algo opuesto al discurso oficial de apertura cultural, y, por otro, una creciente mercantilización de la sociedad y la cultura, en línea con la modernización global. Por su parte, los pobladores originarios muestran recientemente un menor activismo sociocultural y menores niveles de transmisión lingüística y cultural, correlacionando el nivel de participación con el de autoafirmación identitaria, tal y como ocurría en la etapa de promoción de la interculturalidad

A comparative analysis of emissions from bagasse charcoal and wood charcoal

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2005."May 2005."Includes bibliographical references (leaf 27).Haiti is the poorest country in the Western hemisphere and is in need of cheap cooking fuel source. Currently, lump charcoal, the cooking fuel of Haiti, is made by carbonizing trees in ditches before selling the charcoal at market. However, Haiti is now 98% deforested and must find a way to prepare their food that does not destroy their land. The idea for this new fuel comes from compressed and extruded carbonized bagasse, which was produced using an extruder developed in a senior product development class at MIT. Using this bagasse fuel, experiments were conducted to compare the combustion characteristics of the bagasse charcoals with wood charcoal. Unfortunately, the heat released by the bagasse charcoal did not compare favorably with that of the wood charcoal, failing to raise 1 L of water to boiling while the wood charcoal raised the water to boiling for 25 minutes. Since the bagasse charcoal performed similarly to Kingsford brand charcoal, the emissions released were compared between these two fuels. Based on their averages, the bagasse charcoal emitted 1.4 times more CO, 1.6 times more SO₂ and 2.3 times more particulates but only 17% of the NOx emitted by Kingsford.by Andrés Ramírez.S.B

Cross-selling in Colombian pension funds: An approach using survival analysis

El desarrollo de estrategias comerciales para realizar ventas cruzadas efectivas de servicios pensionales, puede ser uno de los retos más grandes de los fondos de pensiones. Se utilizó la base de datos de los afiliados a un fondo de pensiones obligatorias colombiano para implementar varios modelos que describen la incidencia de 4 características propias de los afiliados, sobre la probabilidad de ingresar al fondo de pensiones voluntarias en el siguiente mes. Los modelos se fundamentan en las técnicas de análisis de supervivencia.The development of commercial strategies for effective cross-sell pension services may be one of the biggest challenges of pension funds. The database of the affiliates of a Colombian mandatory pension fund was used to implement several models that describe the incidence of 4 characteristics of affiliates on the probability of entering the voluntary pension fund in the following month. The models are based on the survival analysis techniques