Evaluación y baremación de variables psicosociales a través de una plataforma online

La presente tesis se presenta en dos áreas altamente relacionadas como son la Psicología e Informática prestando atención a la informatización de cuestionarios on-line. Las ventajas y desventajas de usar este tipo de cuestionarios son tratadas, analizando algunos estudios donde la muestra se tomó a través de Internet. Se aborda el cómo los avances tecnológicos ayudan a la sociedad a realizar ciertos trabajos y cómo a su vez facilitan el desarrollo de los mismos. Los problemas metodológicos planteados por las plataformas de investigación on-line son otro punto tratado. Aunque hay estudios que indican que no existen diferencias significativas en la forma de realizar las investigaciones, pueden surgir problemas metodológicos relacionados con las propiedades psicométricas y el uso de Internet como herramienta de investigación. El carácter multidisciplinar de esta investigación, aúna conocimientos y esfuerzos de la Psicología y la Informática para un trabajo común - evaluación de las variables psicosociales a través de una plataforma-. Se pretende abarcar tres vertientes: SOCIAL, TECNOLÓGICA, Y CIENTÍFICA. Se ven las principales funciones y características de la plataforma de evaluación, perfiles de usuario y áreas. Se continúa con una descripción técnica y se analiza la parte administrativa usada por los administradores para realizar distintas investigaciones. Para finalizar se describe el diseño de los cuestionarios anónimos junto al análisis, diseño e implementación de la plataforma. La usabilidad de la plataforma mediante ClustrMaps, Google Analytic, y los sucesos producidos por la misma conforman un aspecto importante. Se ven las entradas de los participantes agrupadas por países o ciudades, datos cronológicos de entrada (día, mes, año, hora, etc.), demográficos y tecnológicos. Para los resultados descriptivos de la investigación se realiza un estudio de la muestra así como un análisis de las diferentes áreas que intervienen. Para los cuestionarios AF5, Burnout, Emd y Servqual se realiza un estudio de las variables psicosociales disponibles en la plataforma, siguiendo con un estudio cronológico de participantes y entradas, concluyendo con el análisis de los tiempos en realizar los cuestionarios junto a la fiabilidad de las diferentes escalas. La comparación entre la evaluación identificativa y anónima se analiza, citando las ventajas e inconvenientes de cada una de ellas. Se define el concepto de deseabilidad social así como se realiza un estudio de fiabilidad en los cuestionaros IPSETA, PID e IPED, realizando comparaciones entre los resultados obtenidos por los participantes identificados y los anónimos. La plataforma ofrece multitud de cuestionarios organizados en áreas y con un perfil adecuado, cualquier usuario puede realizar las investigaciones que se plantean. En este sentido se citan diversos estudios que la han usado a lo largo de estos años y se finaliza con un número importante de investigaciones en curso y proponiendo una batería de investigaciones futuras a realizar derivadas de este trabajo y la posibilidad que ofrece dicha plataforma.

Cross-correlations between weather variables in Australia

The information on climate variations is essential for the research of many subjects, such as the performance of buildings and agricultural production. However, recorded meteorological data are often incomplete. There may be a limited number of locations recorded, while the number of recorded climatic variables and the time intervals can also be inadequate. Therefore, the hourly data of key weather parameters as required by many building simulation programmes are typically not readily available. To overcome this gap in measured information, several empirical methods and weather data generators have been developed. They generally employ statistical analysis techniques to model the variations of individual climatic variables, while the possible interactions between different weather parameters are largely ignored. Based on a statistical analysis of 10 years historical hourly climatic data over all capital cities in Australia, this paper reports on the finding of strong correlations between several specific weather variables. It is found that there are strong linear correlations between the hourly variations of global solar irradiation (GSI) and dry bulb temperature (DBT), and between the hourly variations of DBT and relative humidity (RH). With an increase in GSI, DBT would generally increase, while the RH tends to decrease. However, no such a clear correlation can be found between the DBT and atmospheric pressure (P), and between the DBT and wind speed. These findings will be useful for the research and practice in building performance simulation.

Identification of critical input variables for risk-based cost estimates for road maintenance and rehabilitation

An estimation of costs for maintenance and rehabilitation is subject to variation due to the uncertainties of input parameters. This paper presents the results of an analysis to identify input parameters that affect the prediction of variation in road deterioration. Road data obtained from 1688 km of a national highway located in the tropical northeast of Queensland in Australia were used in the analysis. Data were analysed using a probability-based method, the Monte Carlo simulation technique and HDM-4’s roughness prediction model. The results of the analysis indicated that among the input parameters the variability of pavement strength, rut depth, annual equivalent axle load and initial roughness affected the variability of the predicted roughness. The second part of the paper presents an analysis to assess the variation in cost estimates due to the variability of the overall identified critical input parameters.

Using Trauma Injury Severity Score (TRISS) variables to predict length of hospital stay following trauma in New Zealand

Aim – To develop and assess the predictive capabilities of a statistical model that relates routinely collected Trauma Injury Severity Score (TRISS) variables to length of hospital stay (LOS) in survivors of traumatic injury. Method – Retrospective cohort study of adults who sustained a serious traumatic injury, and who survived until discharge from Auckland City, Middlemore, Waikato, or North Shore Hospitals between 2002 and 2006. Cubic-root transformed LOS was analysed using two-level mixed-effects regression models. Results – 1498 eligible patients were identified, 1446 (97%) injured from a blunt mechanism and 52 (3%) from a penetrating mechanism. For blunt mechanism trauma, 1096 (76%) were male, average age was 37 years (range: 15-94 years), and LOS and TRISS score information was available for 1362 patients. Spearman’s correlation and the median absolute prediction error between LOS and the original TRISS model was ρ=0.31 and 10.8 days, respectively, and between LOS and the final multivariable two-level mixed-effects regression model was ρ=0.38 and 6.0 days, respectively. Insufficient data were available for the analysis of penetrating mechanism models. Conclusions – Neither the original TRISS model nor the refined model has sufficient ability to accurately or reliably predict LOS. Additional predictor variables for LOS and other indicators for morbidity need to be considered.

A comparative study of manufacturing practices and performance variables

The reported study was conducted to compare and contrast current manufacturing practices between two countries, Australia and Malaysia, and identify the practices that significantly influence their manufacturing performances. The results are based on data collected from surveys using a standard questionnaire in both countries. Evidence indicates that product quality and reliability is the main competitive factor for manufacturers. Maintaining a supplier rating system and regularly updating it with field failure and warranty data and making use of product data management are found to be effective manufacturing practices. In terms of the investigated manufacturing performance, Australian manufacturers are marginally ahead of their Malaysian counterparts. However, Malaysian manufacturers came out ahead on most dimensions of advanced quality and manufacturing practices, particularly in the adoption of product data management, effective supply chains and relationships with suppliers and customers.

Generating rules with predicates, terms and variables from the pruned neural networks

Artificial neural networks (ANN) have demonstrated good predictive performance in a wide range of applications. They are, however, not considered sufficient for knowledge representation because of their inability to represent the reasoning process succinctly. This paper proposes a novel methodology Gyan that represents the knowledge of a trained network in the form of restricted first-order predicate rules. The empirical results demonstrate that an equivalent symbolic interpretation in the form of rules with predicates, terms and variables can be derived describing the overall behaviour of the trained ANN with improved comprehensibility while maintaining the accuracy and fidelity of the propositional rules.

Distribution profiles of key weather variables in Australian capital cities : implications for energy efficient building design

Local climate is a critical element in the design of energy efficient buildings. In this paper, ten years of historical weather data in Australia's eight capital cities were profiled and analysed to characterize the variations of climatic variables in Australia. The method of descriptive statistics was employed. Either the pattern of cumulative distribution and/or the profile of percentage distribution are presented. It was found that although weather variables vary with different locations, there is often a good, nearly linear relation between a weather variable and its cumulative percentage for the majority of middle part of the cumulative curves. By comparing the slopes of these distribution profiles, it may be possible to determine the relative range of changes of the particular weather variables for a given city. The implications of these distribution profiles of key weather variables on energy efficient building design are also discussed.

Important omitted spatial variables in safety models: Understanding contributing crash causes at intersections

Advances in safety research—trying to improve the collective understanding of motor vehicle crash causation—rests upon the pursuit of numerous lines of inquiry. The research community has focused on analytical methods development (negative binomial specifications, simultaneous equations, etc.), on better experimental designs (before-after studies, comparison sites, etc.), on improving exposure measures, and on model specification improvements (additive terms, non-linear relations, etc.). One might think of different lines of inquiry in terms of ‘low lying fruit’—areas of inquiry that might provide significant improvements in understanding crash causation. It is the contention of this research that omitted variable bias caused by the exclusion of important variables is an important line of inquiry in safety research. In particular, spatially related variables are often difficult to collect and omitted from crash models—but offer significant ability to better understand contributing factors to crashes. This study—believed to represent a unique contribution to the safety literature—develops and examines the role of a sizeable set of spatial variables in intersection crash occurrence. In addition to commonly considered traffic and geometric variables, examined spatial factors include local influences of weather, sun glare, proximity to drinking establishments, and proximity to schools. The results indicate that inclusion of these factors results in significant improvement in model explanatory power, and the results also generally agree with expectation. The research illuminates the importance of spatial variables in safety research and also the negative consequences of their omissions.