Should we tax overtime, subsidize the wage or subsidize employment?

This paper compares the macroeconomic implications of taxing overtime and using two kinds of subsidies, an employment and a wage subsidy, in a model where team work and commuting costs subject to congestion are key determinants of the choice of the workweek. To obtain reliable estimates, I calibrate the model to the substitutability between the workweek and employment using business cycle information. I find that subsidizing employment can achieve the same employment increase than taxing overtime but at a lower cost in terms of output, productivity, wages and welfare. The wage subsidy that achieves the same employment increase turns out to be very costly from a fiscal point of view, 12.7% of output versus 4.57% of output in the employment subsidy experiment.Overtime taxation, Subsidies, Workweek, Team Work, Commuting costs.

Structured count data regression

Overdispersion in count data regression is often caused by neglection or inappropriate modelling of individual heterogeneity, temporal or spatial correlation, and nonlinear covariate effects. In this paper, we develop and study semiparametric count data models which can deal with these issues by incorporating corresponding components in structured additive form into the predictor. The models are fully Bayesian and inference is carried out by computationally efficient MCMC techniques. In a simulation study, we investigate how well the different components can be identified with the data at hand. The approach is applied to a large data set of claim frequencies from car insurance

Systematics and porphology of the tribe Anisoscelini, Coridae (Heteroptera)

Imperial Users onl

A Comparison of Nature Inspired Algorithms for Multi-threshold Image Segmentation

In the field of image analysis, segmentation is one of the most important preprocessing steps. One way to achieve segmentation is by mean of threshold selection, where each pixel that belongs to a determined class islabeled according to the selected threshold, giving as a result pixel groups that share visual characteristics in the image. Several methods have been proposed in order to solve threshold selectionproblems; in this work, it is used the method based on the mixture of Gaussian functions to approximate the 1D histogram of a gray level image and whose parameters are calculated using three nature inspired algorithms (Particle Swarm Optimization, Artificial Bee Colony Optimization and Differential Evolution). Each Gaussian function approximates thehistogram, representing a pixel class and therefore a threshold point. Experimental results are shown, comparing in quantitative and qualitative fashion as well as the main advantages and drawbacks of each algorithm, applied to multi-threshold problem.Comment: 16 pages, this is a draft of the final version of the article sent to the Journa

An Empirical Study Comparing Unobtrusive Physiological Sensors for Stress Detection in Computer Work.

Several unobtrusive sensors have been tested in studies to capture physiological reactions to stress in workplace settings. Lab studies tend to focus on assessing sensors during a specific computer task, while in situ studies tend to offer a generalized view of sensors' efficacy for workplace stress monitoring, without discriminating different tasks. Given the variation in workplace computer activities, this study investigates the efficacy of unobtrusive sensors for stress measurement across a variety of tasks. We present a comparison of five physiological measurements obtained in a lab experiment, where participants completed six different computer tasks, while we measured their stress levels using a chest-band (ECG, respiration), a wristband (PPG and EDA), and an emerging thermal imaging method (perinasal perspiration). We found that thermal imaging can detect increased stress for most participants across all tasks, while wrist and chest sensors were less generalizable across tasks and participants. We summarize the costs and benefits of each sensor stream, and show how some computer use scenarios present usability and reliability challenges for stress monitoring with certain physiological sensors. We provide recommendations for researchers and system builders for measuring stress with physiological sensors during workplace computer use

Implementing the 35 Hour Workweek by Means of Overtime Taxation

In this paper we study the implications of taxing overtime work in order to reduce the workweek. To this purpose we study the roles played by team work, commuting costs and idiosyncratic output risk in determining the choice of the workweek. In order to obtain reliable estimates of the consequences of our policy experiment, we calibrate our model economy to the substitutability between overtime and employment using business cycle information. We find that a tax-rate of 12% of overtime wages implements the desired reduction of the workweek from 40 to 35 hours (12.5%). We also find that this tax change increases employment by 7% and reduces output and productivity by 10.2% and 4.2%, respectively. We also study a model economy with cross-sectional variations in the workweek that arise from plant-specific output risk and we find that in this model economy the tax-rates needed to achieve the same workweek reduction are significantly larger. Finally, we find that taxing overtime dampens business cycle fluctuations and that its welfare costs seem to be very largeWorkweek, Overtime, 35 Hours week, Labour Policy

A Heuristic Procedure with Guided Reproduction for Constructing Cocyclic Hadamard Matrices

A genetic algorithm for constructing cocyclic Hadamard matrices over a given group is described. The novelty of this algorithm is the guided heuristic procedure for reproduction, instead of the classical crossover and mutation operators. We include some runs of the algorithm for dihedral groups, which are known to give rise to a large amount of cocyclic Hadamard matrices.Ministerio de Ciencia e Innovación MTM2008-06578Junta de Andalucía FQM–296Junta de Andalucía P07-FQM-0298

La importancia de Zenobia Camprubí en el ámbito de la filología

El objetivo de las investigaciones que hemos realizado bajo la perspectiva de género ha consistido en el estudio de mujeres que han contribuido notablemente, de manera directa o indirecta, a la literatura y que no han sido conocidas y/o reconocidas por el “público en general”. En esta ocasión nos vamos a centrar en la figura de Zenobia Camprubí. Para ello, hemos profundizado en el estudio de su vida y actividad investigadora, así como en su poderosa influencia en la literatura a través de la figura de Juan Ramón Jiménez. Todos los datos recopilados, más una amplia galería de fotografías que ilustran distintos momentos de su vida, se han presentado en forma de conferencias participativas en diversos foros: Ciclo de conferencias y mesas redondas conmemorativas del Día de la Mujer en la localidad de Camas en 2006, en la localidad de Bollullos de la Mitación en 2007, en La Algaba en 2008 y con motivo de otras fechas importantes, como el Día del Libro, en Pruna en 2006, en Martín de la Jara y Algámitas en 2007, o Constantina en 2008. Todos estos actos fueron organizados por el Área de Cultura y Deportes de la Diputación de Sevilla