Rainbow matchings in strongly edge-colored graphs

A rainbow matching of an edge-colored graph G is a matching in which no two edges have the same color. There have been several studies regarding the maximum size of a rainbow matching in a properly edge-colored graph G in terms of its minimum degree 3(G). Wang (2011) asked whether there exists a function f such that a properly edge-colored graph G with at least f (delta(G)) vertices is guaranteed to contain a rainbow matching of size delta(G). This was answered in the affirmative later: the best currently known function Lo and Tan (2014) is f(k) = 4k - 4, for k >= 4 and f (k) = 4k - 3, for k <= 3. Afterwards, the research was focused on finding lower bounds for the size of maximum rainbow matchings in properly edge-colored graphs with fewer than 4 delta(G) - 4 vertices. Strong edge-coloring of a graph G is a restriction of proper edge-coloring where every color class is required to be an induced matching, instead of just being a matching. In this paper, we give lower bounds for the size of a maximum rainbow matching in a strongly edge-colored graph Gin terms of delta(G). We show that for a strongly edge-colored graph G, if |V(G)| >= 2 |3 delta(G)/4|, then G has a rainbow matching of size |3 delta(G)/4|, and if |V(G)| < 2 |3 delta(G)/4|, then G has a rainbow matching of size |V(G)|/2] In addition, we prove that if G is a strongly edge-colored graph that is triangle-free, then it contains a rainbow matching of size at least delta(G). (C) 2015 Elsevier B.V. All rights reserved.

Productividad, eficiencia y tecnologías de la información y de la comunicación: Aplicación empírica a la industria española

ste trabajo estudia la contribución de las tecnologías de la información y de la comunicación al crecimiento de la industria española, durante el periodo 1990-1999. Se aplica la descomposición del crecimiento de Solow (1957) y para el análisis de productividad se usa la metodología de fronteras estocásticas. Se encuentra que la mayor contribución es en la producción de las ramas TIC-manufacturas y éstas no tienen efectos spillover significativos. También se destaca el escaso efecto sobre la productividad del progreso técnico incorporado en capital físico.

Uso estratégico de la deuda: un estudio a nivel de empresa para colombia 1995-2003

El presente trabajo intenta estimar si las empresas emplean estratégicamente la deuda para limitar la entrada de potenciales rivales. Mediante la metodología de Método Generalizado de Momentos (GMM) se evalúa el efecto que tienen los activos específicos, la cuota de mercado y el tamaño, como proxies de las rentas del mercado, y las barreras de entrada sobre los niveles de endeudamiento, a nivel de empresa para Colombia, durante 1995-2003. Se encuentra que las empresas utilizan los activos específicos para limitar la entrada al mercado y que el endeudamiento decrece a medida que las empresas aumentan su cuota en el mercado

Introducció al disseny experimental: pràctiques de laboratori i de camp per a biòleg [versió html]

Aquest llibre pretén ser una guia útil per al disseny d'experiments científics en el camp de la biologia, tant pel que fa a les pràctiques de laboratori com al treball de camp. El llibre s'estructura en tres grans apartats: Mètode científic i disseny experimental, Estudi manipulatiu, i Estudi observacional o mesuratiu

Introducció al disseny experimental: pràctiques de laboratori i de camp per a biòlegs [versió pdf]

Aquest llibre pretén ser una guia útil per al disseny d'experiments científics en el camp de la biologia, tant pel que fa a les pràctiques de laboratori com al treball de camp. El llibre s'estructura en tres grans apartats: Mètode científic i disseny experimental, Estudi manipulatiu, i Estudi observacional o mesuratiu

eLEARNING - A CHANCE FOR SMALL AND MEDIUM SIZED ENTERPRISES

eLearning through its flexibility and facility of access is seen as a major enabler of lifelong learning (LLL), as a catalyst of change and a chance for small and medium-sized enterprises (SMEs) to improve their business and to integrate into European market. But so far the eLearning in the context of vocational educational training has been mainly adopted by large enterprises, while only little activity can be observed in SMEs. The question arises what the chances and challenges for SMEs are and what is the experience with its usage. In this paper after a presentation of key issues in eLearning chances and challenges of eLearning for SMEs are discussed and experiences are exemplified by three EU-funded eLearning projects. The focus lies on the ongoing project ARIEL - Analysing and Reporting the Implementation of Electronic Learning in Europe - coordinated by the Institut Arbeit und Technik (IAT).

eLEARNING - EINE CHANCE FÜR KLEINE UND MITTLERE UNTERNEHMEN

eLearning wird durch seine Flexibilität und Zugänglichkeit als bedeutendes Instrument für die Implementierung lebenslangen Lernens (LLL) angesehen. Es kann für kleine und mittelgroße Unternehmen (KMU) einen Katalysator des Wandels sein und bietet damit die Chance zur Verbesserung der wirtschaftlichen Leistungsfähigkeit. Darüber hinaus kann eLearning dazu dienen, die Integration von KMU in den europäischen Markt zu fördern. Bis jetzt wird eLearning im Rahmen der beruflichen Aus- und Weiterbildung jedoch nahezu ausschließlich in Großunternehmen genutzt, während es in KMU allenfalls eine marginale Rolle spielt. Im ersten Kapitel dieses Artikels wird auf den Perspektivenwechsel in der beruflichen Aus- und Weiterbildung eingegangen. Im Anschluss daran werden die zentralen Elemente von eLearning vorgestellt (Kap. 2). Die mit eLearning verbundenen Chancen und Herausforderungen für KMU diskutiert (Kap. 3). Abschließend wird auf Erfahrungen mit eLearning in der Praxis am Beispiel von drei EU-finanzierten Projekten eingegangen. Das Hauptaugenmerk liegt dabei auf dem laufenden Projekt ARIEL -Analysing and Reporting the Implementation of Electronic Learning in Europe -, das vom Institut Arbeit und Technik, Gelsenkirchen, (IAT) koordiniert wird.

An empirical analysis on the efficiency of the microfinance investment market

This paper empirically analyzes the market efficiency of microfinance investment funds. For the empirical analysis, we use an index of the microfinance investment funds and apply two kinds of variance ratio tests to examine whether or not this index follows a random walk. We use the entire sample period from December 2003 to June 2010 as well as two sub-samples which divide the entire period before and after January 2007. The empirical evidence demonstrates that the index does not follow a random walk, suggesting that the market of the microfinance investment funds is not efficient. This result is not affected by changes in either empirical techniques or sample periods.

Financial permeation as a role of microfinance : has microfinance actually been helpful to the poor?

This article is distinct in its application of the logit transformation to the poverty ratio for the purpose of empirically examining whether the financial sector helps improve standards of living for low-income people. We propose the term financial permeation to describe how financial networks expand to spread money among the poor. We measure financial permeation by three indicators related to microfinance institutions (MFIs) and then examine its effect on poverty reduction at the macro level using panel data for 90 developing countries from 1995 to 2008. We find that financial permeation has a statistically significant and robust effect on decreasing the poverty ratio.

How does contract design affect the uptake of microcredit among the ultra-poor? : experimental evidence from the river islands of Northern Bangladesh

Despite the professed claims of microcredit alleviating poverty, little is known about what kind of credit contract is suitable for extremely poor households, also called the ultra-poor. To fill this knowledge gap, we initiated a field experiment in the river islands of northern Bangladesh, where a substantial portion of dwellers could be categorized as ultra-poor due to cyclic floods. We randomly offered four types of loans to such dwellers: regular small cash loans with one-year maturity, large cash loans with three-year maturity both with and without a one-year grace period, and in-kind livestock loans with three-year maturity and a one-year grace period. We compared uptake rates as well as the determinants of uptake and found that the uptake rate is the lowest for the regular contract, followed by the in-kind contract. Contrary to prior belief, we also found that the microcredit demand by the ultra-poor is not necessarily small, and in particular the ultra-poor are significantly more likely to join a microcredit program than the moderately poor if a grace period with longer maturity is attached to a large amount of credit, irrespective of whether the credit is provided in cash or in kind. This paper provides evidence that a typical microcredit contract with one-year maturity and without a grace period is not attractive to the ultra-poor. Microfinance institutions may need to design better credit contracts to address the poor's needs.

The plébiscite ; a miller's story of the war by one of the 7,500.000 who voted yes

UANL

Conducta y juicio moral : el proceso de interiorización de normas entre 3 y 7 años.

Elaborar un modelo de desarrollo moral que de cuenta de las relaciones que se establecen entre la valoración moral de una situación y la conducta moral efectiva frente a esa situación, en edades comprendidas entre los 3 y 7 años. La muestra estaba compuesta por 64 sujetos, 32 varones y 32 hembras, alumnos de Párvulos, primero de EGB y segundo de EGB del Colegio Nacional Dolors Monerda de Barcelona, de nivel socio-económico medio y medio-alto. Se analiza el desarrollo moral desde el enfoque psicoanalítico, el enfoque conductista y el enfoque piagetiano. A continuación se analizan y comparan los trazos fundamentales de la conducta moral, en situaciones controladas, de los sujetos de la muestra entre sí y con los resultados obtenidos en un conjunto de 302 fichas recogidas por padres y profesores, en las cuales se detallan conductas morales, en situaciones no sujetas a control, de sujetos de edades comprendidas entre 1 y 12 años. Entrevista personal. Hay relaciones claramente definibles entre el razonamiento acerca de una situación y la acción efectiva sobre ella. En relación a la evolución moral, se definen tres etapas claramente diferenciadas que se manifiestan tanto a nivel de razonamiento como a nivel de conducta.