Annualized hours as a capacity planning tool in make-to-order or assemble-to-order environment: An agricultural implements company case

Capacity planning is one of the most important elements for an efficient production planning and control system. It is even more important when the main strategies to fulfil sales requirements are make-to-order (MTO) or assemble-to-order (ATO). Neither MTO or ATO companies keep finished products in stock which means that production level is driven by actual sales figures. Therefore, it is very important to have an available capacity as flexible as possible to meet sales requirements. Annualized hours (AH) is a work time control system that helps in increasing the flexibility of available capacity. The main rule of the AH system is to hire employees to work a certain number of hours on a yearly basis. Following some other pre-defined rules and limits, the AH system allows a company to adjust weekly available time in order to reduce idle capacity or to fulfil requirements that could mean overtime. This paper proposes a linear programming model to plan the operations using AH. This model has been implemented in a company that produces agricultural implements, showing that it is very simple to use. It is producing excellent practical results.     

Female Migration and Child Occupation in Rural El Salvador

This article looks at the consequences of migration in terms of child education and child labor using a unique rural panel dataset for El Salvador. Results suggest gender differences in the consequences of migration on child activities that remain in El Salvador. While female migration tends to reduce child labor, both in domestic and non-domestic activities, male migration seems to stimulate it, in particular in terms of domestic labor. In contrast, while male migration has null or slightly positive impact in terms of school enrollment rates, female migration apparently reduces the likelihood that a particular child stays at school. Some of these results differ according to the gender of the child. The results do not seem to be driven by female migrants remitting more than males, but rather to alternative competing explanations, such as the existence of child–adult male labor substitution, differences in the use of remittances by gender of the recipient person, or limited ability to monitor funds when remitted by female migrants.     

Testing the equality among distribution functions from independent and right censored samples via Cramér–von Mises criterion

The traditional Cramér–von Mises criterion is used in order to develop a test to compare the equality of the underlying lifetime distributions in the presence of independent censoring times. Its asymptotic distribution is proved and a resampling plan, which is valid for unbalanced data situations, is proposed. Its statistical power is studied and compared with commonly used linear rank tests by Monte Carlo simulations and a real data analysis is also considered. It is observed that the new test is clearly more powerful than the traditional ones when there exists no uniform dominance among involved distributions and in the presence of late differences. Its statistical power is also good in the other considered scenarios.     

The case of post-acquisition integration design decisions

In a multi-method study that examined post-acquisition integration design decisions, managers were found to have poor insight into the values underlying their decision making. This lack of insight was not found to be moderated by increased levels of experience with acquisition decision making, and its effects were reflected in post-acquisition performance.     

DISTRIBUTIONAL INCENTIVES IN AN EQUILIBRIUM MODEL OF DOMESTIC SOVEREIGN DEFAULT

Europe's debt crisis resembles historical episodes of outright default on domestic public debt about which little research exists. This paper proposes a theory of domestic sovereign default based on distributional incentives affecting the welfare of risk‐averse debt and nondebtholders. A utilitarian government cannot sustain debt if default is costless. If default is costly, debt with default risk is sustainable, and debt falls as the concentration of debt ownership rises. A government favoring bond holders can also sustain debt, with debt rising as ownership becomes more concentrated. These results are robust to adding foreign investors, redistributive taxes, or a second asset.     

Expanded renal transplantation: a competing risk model approach

Multi-state models (MSMs) are useful to analyze survival data when, besides the event of main interest, one or more intermediate states of the individual are identified. These models take the several existing states and the possible transitions among them into account. At the same time, covariate effects on each transition intensity may be investigated separately and, therefore, MSMs are more flexible than the standard Cox proportional hazards model. In this work, we use MSMs to investigate the impact of the quality of a transplanted kidney for a group of patients at the Hospital Universitario Central de Asturias. Specifically, we use an illness-death model to study the evolution of patients with kidney disease who received a renal transplant after a dialysis period. The intermediate state is defined as the failure of the received organ, while the terminating state is the death of the patient. In order to increase the potential number of organs available for transplant, the standards of quality for the transplanted kidneys were relaxed (the new criteria are labeled expanded criteria), and these ‘expanded kidneys’ were transplanted in appropriate candidates (older patients, with higher prevalence of diabetes mellitus). Results suggest that the expanded kidneys have a minor effect on survival, while both the kidney mortality and the risk of death increase with the patient's age and the serum creatinine and serum hemoglobin levels.     

El emplazamiento de la memoria colectiva: Crónica Psicosocial

Resumen

El presente trabajo estudia la influencia de la «discusión grupal» sobre los estados afectivos inducidos. Se esperaba que, después de inducir estados afectivos (positivo vs negativo vs neutro) mediante la visión de secuencias de películas, el contexto de discusión grupal (positivo vs negativo), acentuara o atenuara el efecto del método de inducción. Para ello, se utilizó un diseño experimental en el que participaron un total de 60 sujetos, y en el que se analizaron las respuestas de cada grupo experimental en una tarea de asociación libre de palabras. Nuestros resultados demuestran que el efecto del contexto grupal es más potente que el de la visión de películas cortas, originando un número significativamente mayor de palabras originales en el primer caso que en el segundo. Estos resultados son analizados a la luz de recientes teorías sobre cognición y afecto.     

Nonparametric particle filtering approaches for identification and inference in nonlinear state-space dynamic systems

Most system identification approaches and statistical inference methods rely on the availability of the analytic knowledge of the probability distribution function of the system output variables. In the case of dynamic systems modelled by hidden Markov chains or stochastic nonlinear state-space models, these distributions as well as that of the state variables themselves, can be unknown or untractable. In that situation, the usual particle Monte Carlo filters for system identification or likelihood-based inference and model selection methods have to rely, whenever possible, on some hazardous approximations and are often at risk. This review shows how a recent nonparametric particle filtering approach can be efficiently used in that context, not only for consistent filtering of these systems but also to restore these statistical inference methods, allowing, for example, consistent particle estimation of Bayes factors or the generalisation of model parameter change detection sequential tests. Real-life applications of these particle approaches to a microbiological growth model are proposed as illustrations.     

The Ranking of the Regions With Regard to Their Sports Facilities to Improve Their Planning in Sport: The Case of Spain

Sports facility planning by the public authorities should be considered to be one of the main policies to have an indirect influence on the aim of ensuring a healthy population, as well as reducing its physical inactivity. Our research aims to study and compare the state of sports infrastructures in the regions of Spain, using a synthetic indicators. Our results should serve not only to detect the vast imparity between different regions, which has come about because of varying investment and management with regard to sports infrastructures, but also to redirect building planning and sports management policies onto the right path, and also give food for thought.     

The Kumaraswamy distribution: median-dispersion re-parameterizations for regression modeling and simulation-based estimation

The Kumaraswamy distribution is very similar to the Beta distribution, but has the important advantage of an invertible closed form cumulative distribution function. The parameterization of the distribution in terms of shape parameters and the lack of simple expressions for its mean and variance hinder, however, its utilization with modeling purposes. The paper presents two median-dispersion re-parameterizations of the Kumaraswamy distribution aimed at facilitating its use in regression models in which both the location and the dispersion parameters are functions of their own distinct sets of covariates, and in latent-variable and other models estimated through simulation-based methods. In both re-parameterizations the dispersion parameter establishes a quantile-spread order among Kumaraswamy distributions with the same median and support. The study also describes the behavior of the re-parameterized distributions, determines some of their limiting distributions, and discusses the potential comparative advantages of using them in the context of regression modeling and simulation-based estimation.