Riesgo a los trastornos de la conducta alimentaria y dimensiones psicopatológicas

An increase in eating disorders and their diversity has been observed over recent decades. Nevertheless, there is a lack of knowledge on the stage that precedes the onset of eating disorders, in which educative programs can prevent successfully these disorders. The present work attempts to describe the relationship between the risk of suffering an eating disorder and certain psychopathological dimensions, and to determine which of these factors contributes to putting the adolescents in a situation where they are at risk of suffering the disorder. A total of 404 students residing in Barcelona, Spain, and aged between 12 and 20 years, were studied. The students were given the Eating Attitudes Test and the Revised Symptom Checklist 90, plus a questionnaire on demographic and family details. A 25.2% risk of eating disorders was detected. This was significantly greater in girls between 12 and 15 years of age, although a high presence of eating disorders risk was detected in males compared to previous studies. It was observed that the group of adolescents at risk of eating disorders has significantly higher levels in all the psychopathological dimensions, mainly phobic anxiety, interpersonal sensitivity and somatisation.En las últimas décadas se ha producido un incremento de los trastornos alimentarios y su diversidad. No obstante, falta más información sobre los estadios precedentes al inicio del trastorno, en los que los programas educativos pueden prevenir exitosamente estos trastornos. El presente trabajo se propone describir la relación entre el riesgo a sufrir un trastorno alimentario y determinadas dimensiones psicopatológicas, y determinar cuáles de estos factores contribuyen en situar a los adolescentes en riesgo a sufrir dichos trastornos. Un total de 404 estudiantes residentes en Barcelona, España, con edades entre los 12 y los 20 años fueron estudiados. Los estudiantes completaron el Test de actitudes alimentarias y el Symptom Checklist 90 (SCL 90), además de un cuestionario demográfico con detalles familiares. Un total de 25.2% de riesgo hacia el trastorno alimentario fue detectado. Este riesgo fue mayor en chicas de entre los 12 y los 15 años, aunque también se detectó un alto porcentaje de riesgo entre chicos comparado con estudios anteriores. Se observó que el grupo de riesgo obtuvo puntuaciones significativamente superiores en todas las dimensiones psicopatológicas, especialmente la ansiedad fóbica, la sensibilidad interpersonal y la somatización

Agradecimiento a los Evaluadores

Los editores de la revista Rect@ quieren agradecer la labor realizada por los evaluadores de los trabajos de los números 10 y 1

Optimization of the Heating System Use in Aged Public Buildings via Model Predictive Control

This work presents the implementation of a Model Predictive Control (MPC) scheme used to study the improvement of the thermal quality in aged residential buildings without any rehabilitation. The controller manages the heating system of an experimentally characterized model of a residential dwelling in a social block built during the decade of the 1960s located in the neighborhood of Otxarkoaga (Bilbao, Spain), so as to obtain an optimal energy efficiency performance. Due to the characteristics of the construction in those days, this kind of buildings suffer problems related to the use of awkward building materials and inefficient heating systems. A comparison with traditionally used ON-OFF hysteresis control is presented in order to demonstrate the energetic improvement provided by the MPC scheme. Besides, the variation of different parameters of the MPC is also studied to determine its influence over the energy consumption and comfort conditions.The authors would like to acknowledge the collaboration of the Basque Energy Board (EVE) through Agreement UPV/EHUEVE23/6/2011 and the Spanish National Fusion Laboratory (CIEMAT) UPV/EHUCIEMAT08/190. Authors are also very grateful for the partial financial contribution to the UPV/EHU and EJ/GV through projects GIU14/07 and IT987-16, as well as to the FEDER and MINECO through project DPI2015-70075-R

A comparison of parametric models for mortality graduation. Application to mortality data of the Valencia Region

[EN] The parametric graduation of mortality data has as its objective the satisfactory estimation of the death rates based on mortality data but using an age-dependent function whose parameters are adjusted from the crude rates obtainable directly from the data. This paper proposes a revision of the most commonly used parametric methods and compares the results obtained with each of them when they are applied to the mortality data for the Valencia Region. As a result of the comparison, we conclude that the Gompertz-Makeham functions estimated by means of generalized linear models lead to the best results. Our working method is of additional interest for being applicable to mortality data for a wide range of ages from any geographical conditions, allowing us to select the most appropriate life table for the case in hand.Debón Aucejo, AM.; Montes-Suay, F.; Sala-Garrido, R. (2005). A comparison of parametric models for mortality graduation. Application to mortality data of the Valencia Region. SORT. Statistics and Operations Research Transactions. 29(2):269-288. http://hdl.handle.net/10251/147780S26928829

A Comparison of Nonparametric Methods in the Graduation of Mortality: Application to Data from the Valencia Region (Spain)

[EN] The nonparametric graduation of mortality data aims to estimate death rates by carrying out a smoothing of the crude rates obtained directly from original data. The main difference with regard to parametric models is that the assumption of an age-dependent function is unnecessary, which is advantageous when the information behind the model is unknown, as one cause of error is often the choice of an inappropriate model. This paper reviews the various alternatives and presents their application to mortality data from the Valencia Region, Spain. The comparison leads us to the conclusion that the best model is a smoothing by means of Generalised Additive Models (GAM) with splines. The most interesting part of this paper is the development of a plan that can be applied to mortality data for a wide range of age groups in any geographical area, allowing the most appropriate table to be chosen for the data in hand.The authors are indebted to the anonymous referees whose suggestions improved the original manuscript. This work was partially supported by a grant from MEyC (Ministerio de Educación y Ciencia, Spain, project MTM-2004-06231).The research of Francisco Montes has also been partially supported by a grant from DGITT (Direcció General d Investigació i Transferència Tecnològica de la Generalitat Valenciana, Project GRUPOS03/189).Debón Aucejo, AM.; Montes-Suay, F.; Sala-Garrido, R. (2006). A Comparison of Nonparametric Methods in the Graduation of Mortality: Application to Data from the Valencia Region (Spain). International Statistical Review. 74(2):215-233. https://doi.org/10.1111/j.1751-5823.2006.tb00171.xS215233742Bloomfield, D. S. F., & Haberman, S. (1987). Graduation: some experiments with kernel methods. Journal of the Institute of Actuaries, 114(2), 339-369. doi:10.1017/s0020268100019090Breiman, L., & Peters, S. (1992). Comparing Automatic Smoothers (A Public Service Enterprise). International Statistical Review / Revue Internationale de Statistique, 60(3), 271. doi:10.2307/1403679Brockmann, M., Gasser, T., & Herrmann, E. (1993). Locally Adaptive Bandwidth Choice for Kernel Regression Estimators. Journal of the American Statistical Association, 88(424), 1302-1309. doi:10.1080/01621459.1993.10476411Chan,, F. Y., Chan, L. K., Falkenberg, J., & Yu, M. H. (1986). Applications of linear and quadratic programmings to some cases of the Whittaker-Henderson graduation method. Scandinavian Actuarial Journal, 1986(3-4), 141-153. doi:10.1080/03461238.1986.10413805Clements, M. S. (2005). Lung cancer rate predictions using generalized additive models. Biostatistics, 6(4), 576-589. doi:10.1093/biostatistics/kxi028Cleveland, W. S. (1979). Robust Locally Weighted Regression and Smoothing Scatterplots. Journal of the American Statistical Association, 74(368), 829-836. doi:10.1080/01621459.1979.10481038Copas, J. B., & Haberman, S. (1983). Non-parametric graduation using kernel methods. Journal of the Institute of Actuaries, 110(01), 135-156. doi:10.1017/s0020268100041275Epanechnikov, V. A. (1969). Non-Parametric Estimation of a Multivariate Probability Density. Theory of Probability & Its Applications, 14(1), 153-158. doi:10.1137/1114019Felipe, A., Guillen, M., & Perez-Marin, A. M. (2002). Recent Mortality Trends in the Spanish Population. British Actuarial Journal, 8(4), 757-786. doi:10.1017/s1357321700003901Forfar, D. O., McCutcheon, J. J., & Wilkie, A. D. (1988). On graduation by mathematical formula. Journal of the Institute of Actuaries, 115(1), 1-149. doi:10.1017/s0020268100042633Gasser, T., Kneip, A., & Köhler, W. (1991). A Flexible and Fast Method for Automatic Smoothing. Journal of the American Statistical Association, 86(415), 643-652. doi:10.1080/01621459.1991.10475090Gasser, T., & Müller, H.-G. (1979). Kernel estimation of regression functions. Smoothing Techniques for Curve Estimation, 23-68. doi:10.1007/bfb0098489Gavin, J. B., Haberman, S., & Verrall, R. J. (1994). On the choice of bandwidth for kernel graduation. Journal of the Institute of Actuaries, 121(1), 119-134. doi:10.1017/s0020268100020102Guillen, M., Nielsen, J. P., & Perez-Marin, A. M. (2006). Multiplicative Hazard Models for Studying the Evolution of Mortality. Annals of Actuarial Science, 1(1), 165-177. doi:10.1017/s1748499500000099Heligman, L., & Pollard, J. H. (1980). The age pattern of mortality. Journal of the Institute of Actuaries, 107(1), 49-80. doi:10.1017/s0020268100040257Hoem, J. M., & Linnemann, P. (1988). The tails in moving average graduation. Scandinavian Actuarial Journal, 1988(4), 193-229. doi:10.1080/03461238.1988.10413848McCullagh, P., & Nelder, J. A. (1989). Generalized Linear Models. doi:10.1007/978-1-4899-3242-6Nadaraya, E. A. (1964). On Estimating Regression. Theory of Probability & Its Applications, 9(1), 141-142. doi:10.1137/1109020Nielsen, J. P. (2003). Smoothing and Prediction with a View to Actuarial Science, Biostatistics and Finance. Scandinavian Actuarial Journal, 2003(1), 51-74. doi:10.1080/03461230308484Silverman, B. W. (1984). A Fast and Efficient Cross-Validation Method for Smoothing Parameter Choice in Spline Regression. Journal of the American Statistical Association, 79(387), 584-589. doi:10.1080/01621459.1984.10478084Verrall, R. J. (1993). Graduation by dynamic regression methods. Journal of the Institute of Actuaries, 120(1), 153-170. doi:10.1017/s002026810003688xWang, J.-L., Müller, H.-G., & Capra, W. B. (1998). Analysis of oldest-old mortality: lifetables revisited. The Annals of Statistics, 26(1), 126-163. doi:10.1214/aos/1030563980Whittaker, E. T. (1922). On a New Method of Graduation. Proceedings of the Edinburgh Mathematical Society, 41, 63-75. doi:10.1017/s0013091500077853Zhang, H. (2004). Mixed effects multivariate adaptive splines model for the analysis of longitudinal and growth curve data. Statistical Methods in Medical Research, 13(1), 63-82. doi:10.1191/0962280204sm353r

Eco‑efficiency assessment under natural and managerial disposability : an empirical application for Chilean water companies

Getting a good understanding regarding the economic and environmental performance of water utilities is of great importance to achieve the goal of an efcient and sustainable industry. In this study, we apply the range adjusted measure (RAM) data envelopment analysis (DEA) model to evaluate the integrated (production and environmental) efciency of several water utilities located in Chile. Integrated efciency is evaluated using the concepts of natural and managerial disposability. This approach further allows us to quantify the contribution of each input and undesirable product on efciency scores. The results highlighted that the Chilean water industry showed high levels of production and environmental efciency over time. Under natural disposability, water utilities could control production costs to reduce water leakage and unplanned water supply interruptions by 3.3% on average. Under managerial disposability, water utilities could further cut down undesirable outputs by 1.4% on average by adopting best managerial practices. On average, potential savings in operating costs, employment, water leakage, and unplanned water supply interruptions were higher for concessionary utilities as they showed slightly lower efciency scores than full private utilities

A comprehensive assessment of energy efficiency of wastewater treatment plants: An efficiency analysis tree approach

Wastewater treatment plants (WWTPs) are energy intensive facilities. Controlling energy use in WWTPs could bring substantial benefits to people and environment. Understanding how energy efficient the wastewater treatment process is and what drives efficiency would allow treating wastewater in a more sustainable way. In this study, we employed the efficiency analysis trees approach, that combines machine learning and linear programming techniques, to estimate energy efficiency of wastewater treatment process. The findings indicated that considerable energy inefficiency among WWTPs in Chile existed. The mean energy efficiency was 0.287 suggesting that energy use should cut reduce by 71.3 % to treat the same volume of wastewater. This was equivalent to a reduction in energy use by 0.40 kWh/m3 on average. Moreover, only 4 out of 203 assessed WWTPs (1.97 %) were identified as energy efficient. It was also found that the age of treatment plant and type of secondary technology played an important role in explaining energy efficiency variations among WWTPs

Monetary valuation of unsorted waste: A shadow price approach

Producción CientíficaImproving the management of municipal solid waste (MSW) is fundamental to promote circular economy and sustainability. Unsorted waste involves negative environmental impacts which often are ignored in economic feasibility studies due to its difficult valuation. In this study the shadow price of unsorted waste using the directional distance function was estimated. This methodological approach also allowed us to compute eco-efficiency scores of a set of municipalities in the provision of MSW services. The empirical application focused on a sample of 119 Chilean municipalities. The results showed that the average shadow price of unsorted waste was 297.66 €/ton which means that the environmental cost of left waste as unsorted was 297.66 € per ton. A regression tree model illustrated that population density, tourism intensity and the generation of waste per capita significantly influenced the shadow price of unsorted waste. Moreover, it was illustrated that Chilean municipalities were very inefficient in the management of MSW since the average eco-efficiency score was 0.272. The findings from this study reveal that additional and alternative policies should be adopted to improve the management of MSW and increase its recycling rate.Agencia Nacional de Investigación y Desarrollo -Fondo Nacional de Desarrollo Científico y Tecnológico (project 1210077

Accounting for service quality to customers in the efficiency of water companies: evidence from England and Wales

This paper investigates the role of service quality to customers in the efficiency assessment of water companies in England and Wales. To achieve this, data envelopment analysis techniques are employed to compute the technical efficiency of the water companies following two approaches: (i) traditional assessment based on quantity variables (without the inclusion of service quality variables) and (ii) alternative assessment considering quantity and service quality variables as undesirable outputs. The analysis covers 22 water and sewerage companies and water only companies providing drinking water services. The results indicate that the traditional efficiency assessment reveals a high level of technical efficiency, suggesting that the English and Welsh water industry is mature and that one of the challenges it faces is improving service quality. When introducing service quality variables in the evaluation, the average scores of technical efficiency slightly decrease. This suggests that, on average, water companies do not necessarily provide high quality of service, meaning that the traditional efficiency assessment favours their performance. Quality of service supplied to customers within a water sector matters and should be taken into account during the benchmarking process as it could assist regulated companies and regulators to improve performance and incentives, respectively

Assesing the influence of environmental variables on the performance of water companies: An efficiency analysis tree approach

Producción CientíficaEfficiency assessment is a valuable tool for industries that are regulated, such as the provision of drinking water. Hence, past research on this topic is wide. However, current, widely used approaches such as parametric, non-parametric and partial frontier methods present several limitations and pitfalls. Thus, here, the Efficiency Analysis Tree (EAT) method was trialled on a sample of water companies. This method overcomes overfitting issues, because it employs a combination of classification, regression tree methods, and non-parametric analyses. For comparative purposes, efficiency was also estimated using Data Envelopment Analysis (DEA) and Free Disposal Hull (FDH) non-parametric methods. The approach was applied empirically using a sample of English and Welsh water companies during 1991–2020. Average efficiency was estimated at 0.489, showing that water companies could save 51.1% of their costs if efficient. Except for the 2011–2015 period, efficiency increased over time, indicating that price reviews by the English and Welsh water regulator contributed to improving water company performance. The application of bootstrap regression analysis techniques showed that the main source of raw water, percentage of metered properties, population density, and percentage of water leakage represented environmental variables that significantly influenced the efficiency scores of water companies. The approach introduced here could be of use to water regulators, as it overcomes the existing limitations of traditional approaches employed to assess the performance of water companies, facilitating sound decision-making