A multivariate generalized independent factor GARCH model with an application to financial stock returns

We propose a new multivariate factor GARCH model, the GICA-GARCH model , where the data are assumed to be generated by a set of independent components (ICs). This model applies independent component analysis (ICA) to search the conditionally heteroskedastic latent factors. We will use two ICA approaches to estimate the ICs. The first one estimates the components maximizing their non-gaussianity, and the second one exploits the temporal structure of the data. After estimating the ICs, we fit an univariate GARCH model to the volatility of each IC. Thus, the GICA-GARCH reduces the complexity to estimate a multivariate GARCH model by transforming it into a small number of univariate volatility models. We report some simulation experiments to show the ability of ICA to discover leading factors in a multivariate vector of financial data. An empirical application to the Madrid stock market will be presented, where we compare the forecasting accuracy of the GICA-GARCH model versus the orthogonal GARCH one

A multivariate generalized independent factor GARCH model with an application to financial stock returns

We propose a new multivariate factor GARCH model, the GICA-GARCH model , where the data are assumed to be generated by a set of independent components (ICs). This model applies independent component analysis (ICA) to search the conditionally heteroskedastic latent factors. We will use two ICA approaches to estimate the ICs. The first one estimates the components maximizing their non-gaussianity, and the second one exploits the temporal structure of the data. After estimating the ICs, we fit an univariate GARCH model to the volatility of each IC. Thus, the GICA-GARCH reduces the complexity to estimate a multivariate GARCH model by transforming it into a small number of univariate volatility models. We report some simulation experiments to show the ability of ICA to discover leading factors in a multivariate vector of financial data. An empirical application to the Madrid stock market will be presented, where we compare the forecasting accuracy of the GICA-GARCH model versus the orthogonal GARCH one.ICA, Multivariate GARCH, Factor models, Forecasting volatility

Exploring ICA for time series decomposition

In this paper, we apply independent component analysis (ICA) for prediction and signal extraction in multivariate time series data. We compare the performance of three different ICA procedures, JADE, SOBI, and FOTBI that estimate the components exploiting either the non-Gaussianity, or the temporal structure of the data, or combining both, non-Gaussianity as well as temporal dependence. Some Monte Carlo simulation experiments are carried out to investigate the performance of these algorithms in order to extract components such as trend, cycle, and seasonal components. Moreover, we empirically test the performance of those three ICA procedures on capturing the dynamic relationships among the industrial production index (IPI) time series of four European countries. We also compare the accuracy of the IPI time series forecasts using a few JADE, SOBI, and FOTBI components, at different time horizons. According to the results, FOTBI seems to be a good starting point for automatic time series signal extraction procedures, and it also provides quite accurate forecasts for the IPIs.ICA, Signal extraction, Multivariate time series, Forecasting

Exploring ICA for time series decomposition

In this paper, we apply independent component analysis (ICA) for prediction and signal extraction in multivariate time series data. We compare the performance of three different ICA procedures, JADE, SOBI, and FOTBI that estimate the components exploiting either the non-Gaussianity, or the temporal structure of the data, or combining both, non-Gaussianity as well as temporal dependence. Some Monte Carlo simulation experiments are carried out to investigate the performance of these algorithms in order to extract components such as trend, cycle, and seasonal components. Moreover, we empirically test the performance of those three ICA procedures on capturing the dynamic relationships among the industrial production index (IPI) time series of four European countries. We also compare the accuracy of the IPI time series forecasts using a few JADE, SOBI, and FOTBI components, at different time horizons. According to the results, FOTBI seems to be a good starting point for automatic time series signal extraction procedures, and it also provides quite accurate forecasts for the IPIs

Designing training for teaching environmental toxicology to specialized pharmacists

ntroduction: The Toxicology Unit at the University of Alcala (Spain) started to provide a novel short-term training course in environmental toxicology for pharmacists enrolled in the postgraduate specialty "Specialist in Industrial Pharmacy and Galenicals" in 2013-2014. This specialty is only available to state-board certified pharmacists considering enrolling in a specialized health training program. Objective: The objective was to create a short, dynamic, and interactive highly specialized training workshop to introduce future professionals to the subject of environmental toxicology and public health. The success of this novel short training course and the interest of the students in environmental toxicology were also analyzed. Methods: A specialized training workshop in environmental toxicology was developed for pharmacists who often have a limited knowledge of environmental health. The training workshop consisted of both theoretical and practical sessions. The practical exercise was highly dynamic and involved identifying potential human risks from pharmaceuticals and care products in water environments as well as the development of a protection and remediation strategy. Results: Following successful training pharmacists demonstrated good understanding of the source-pathway-receptor model and were capable of tailoring strategies to protect human health and future generations. Conclusions: The novel short training course was successful in developing postgraduate students' knowledge of environmental toxicology by providing a practical introduction to environmental health. The methods described here may be used for designing longer training events or courses of environmental toxicology for pharmacists who wish to work in the industry

Reduced graphene oxide improves the performance of a methanogenic biocathode

.Microbial electrosynthesis (MES), a sub-branch of bioelectrochemical processes, takes advantage of a certain type of electroactive microorganism to produce added value products (such as methane) from carbon dioxide (CO2). The aim of this study is to quantify the benefits of using a carbon felt electrode modified with reduced graphene-oxide (rgoCF) as a methanogenic biocathode. The current density generated by the rgoCF was almost 30% higher than in the control carbon felt electrode (CF). In addition, charge transfer and ohmic resistances were, on average, 50% lower in the rgoCF electrode. These improvements were accompanied by a larger presence of bacteria (31% larger) and archaea (18% larger) in the rgoCF electrode. The microbial communities were dominated by hydrogenotrophic methanogenic archaea (Methanobacterium) and, to a lesser extent, by a low-diversity group of bacteria in both biocathodes. Finally, it was estimated that for a CO2 feeding rate in the range 15–30 g CO2 per m2 of electrode per day, it is possible to produce a high-quality biogas (>95% methane concentrationS

Mental mapping: graphic organization as didactical strategy for the construction of knowledge

En este trabajo, buscamos registrar el impacto de los mapas mentales como organizadores gráficos en la construcción del conocimiento. Realizamos la investigación con 140 estudiantes universitarios de segundo curso de la Titulación de Magisterio, en la especialidad de Educación Primaria. Optamos por el modelo cualitativo de investigación, al aplicar un cuestionario autorreflexivo al alumnado; para el procesamiento de los datos, utilizamos el programa Atlas.ti. Señalamos, como síntesis, que el mapa mental, además de contribuir al desarrollo total de la persona, conecta con el enfoque multisensorial y constituye un “organizador gráfico” para la construcción del pensamientoIn this paper, we seek to register the impact of mental maps and graphic organizers in the construction of knowledge. Research conducted with 140 university students from the second year of the Education Degree, majoring in Elementary Education. We chose the qualitative research model, applying a self-reflective questionnaire to the students. For data processing, we used the program Atlas.ti. In conclusion, we put forward that the mental map, apart from contributing to the overall development of the person, connects to the multisensory approach and works as a “graphic organizer” for the construction of though