Skewness in Financial Returns: Evidence from the Portuguese Stock Market (in English)

This paper addresses the issue of symmetry in financial returns. The return distributions of the major stocks traded on the Portuguese market and included in the PSI-20 Index are examined for periods from four to nine years. The results show that the symmetry of the returns is rejected against several alternative distributions. Statistically significant differences between returns below and above the mean are detected, which provides additional evidence of skewness in the return distributions. In addition, as observed in other studies, it is interesting to note that such results are similar to other low-capitalization and low-volume markets, which also exhibit asymmetric return distributions.stock markets, skewness, financial returns

Frangos de corte: controle de qualidade de matérias primas e rações

TCC (graduação em Agronomia) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, 200

The pricing of loans to LBOs in the U.S. versus Europe

This thesis investigates the determinant factors concerning pricing of loans in LBOs, using a sample of 13,315 syndicated loans closed from 2000 to 2013. The results seem to indicate that spreads and pricing processes differ significantly in market-based versus bank-based financial systems as well as in the U.S. versus W.E. In the pre-crisis period, LBO loans extended to market-based borrowers face higher spreads compared to bank-based countries. During the crisis-period, borrowers from common law legal systems face higher spreads for loans in LBOs. The regression results presented for LBO loans extended to U.S. versus W.E. borrowers demonstrate that those in the U.S. face higher spreads. These results are in line with Carey and Nini (2007). A robust convex relationship between spread and maturity is found for loans in LBOs. Lastly, acquired firms with higher cash flow potential (market-to-book ratio) and asset tangibility (fixed asset to total assets) experience a lower spread. Furthermore, firms’ characteristics, namely book leverage, do not affect the pricing of loans in LBOs, opposed to marketability and default factors

Modelling eating behaviours : from childhood to adolescence

PhD ThesisThis thesis aimed to explore the relationships between predictors1 of eating behaviours in both childhood and adolescence and investigate their influence on food choice and food intake. For this, a global approach was used integrating individual, social and environmental predictors. The data included 210 participants aged 6-8 years old and 303 at the age of 12-13 of the Gateshead Millennium Study. Section II (Food intake in childhood) aimed to explore the relationships between predictors (e.g. trying and liking fruits and vegetables, parents’ food intake, etc.) and how they influence food intake in childhood (6-8 years old). Higher intake of healthy food was directly associated to liking fruits/vegetables and lower deprivation level, whereas higher intake of unhealthy was directly associated to lower level of liking fruits and lower BMI. Section III (Food choice and food intake in adolescence) aimed to explore the relationships between predictors (e.g. intention and temptation to eat healthy and unhealthy food, inhibitory control, etc.) and how they influence food choice and food intake in adolescence (12-13 years old). Temptation was the strongest predictor of the food choice, whereas inhibitory control was the only predictor of healthy intake. None of the predictors influenced unhealthy intake. Section IV (Longitudinal analysis) aimed to explore how food intake and its predictors in childhood influence eating behaviours and their predictors in adolescence. Tracking was weak in unhealthy intake and moderate in healthy intake. Several relationships between predictors from childhood influencing directly or indirectly eating behaviours in adolescence were found. This thesis gives some evidence of the complexity of eating behaviours in childhood and adolescence. Some limitations and implications for practice and future research are discussed

Termografia: uma ferramenta de apoio ao diagnóstico de avarias

Desde que saiu do secretismo militar, nas últimas décadas do século passado, a termografia infravermelha, tem vindo a ampliar a sua aplicação em todas as áreas. A experiência de obtenção de assinaturas térmicas de equipamentos militares e de toda a actividade militar, foram transpostas para outras áreas de actividade e com elas todas as ferramentas de análise. O desenvolvimento e vulgarização da informática e a concorrência entre marcas, com a consequente diminuição de custos, facilitou a sua divulgação. Na manutenção preventiva, quando correctamente utilizada, a termografia infravermelha, é um excelente auxiliar, tendo a vantagem de ser uma ferramenta segura, versátil, de não contacto e que proporciona grande rapidez de observação. No presente trabalho é passado em revisão o estado da arte no campo específico do tema da dissertação e foram estudados os princípios da termografia. Foram realizados três trabalhos de campo, traduzidos por outras tantas inspecções termográficas em empresas metolomecânicas e foram recolhidas imagens de exterior do edifício do ISEL e do parque de estacionamento. Foram ainda realizados ensaios de laboratório sobre desalinhamento angular onde foram obtidas imagens termográficas da fase de arranque até ao aquecimento do modelo com os veios alinhados a duas rotações distintas e com dois desalinhamentos angulares diferentes. Foi ainda executado um terceiro ensaio com os veis desalinhados, para confirmação de valores. Face aos resultados, o natural desenvolvimento deste trabalho aponta para a continuação dos ensaios neste campo de forma a confirmar os valores obtidos e estabelecer factores de correcção para diferentes condições de desalinhamento e temperatura ambiente

A multibody approach to the contact dynamics: a knee joint application

In this thesis, a general approach for dynamic analysis of multibody systems with contact is presented, being a special attention given to the articular contact at the human knee joint. Two methodologies, in two- and three-dimensions, for knee contact modeling are proposed under the framework of multibody systems using generalized Cartesian coordinates. The development of the planar multibody knee model encompasses four steps: (i) geometrical representation of contacting profiles by means of curve fitting techniques based on spline interpolation functions; (ii) location of contact points and evaluation of the contact indentation; (iii) calculation of the contact forces by using an appropriate constitutive law; (iv) description of the ligament behavior by a quadratic stress-strain relation. The motion of the tibia relative to the femur is modeled combining the action of the knee ligaments with the potential contacts between the bones. The contact forces, together with the forces produced by the ligaments, are introduced into the Newton-Euler equations of motion as external generalized forces. Within the three-dimensional methodology, the contact surfaces are described by means of point-clouds extracted from parametric representations. The spatial formulation presents a pre-processing unit. This preprocessor allows for a significantly reduction of the amount of memory required for data storage and an improvement of the computational efficiency of the contact detection process. Computational simulations were performed with the aim of validating both proposed approaches, two-dimensional and three-dimensional. The behavior of the planar knee model resultant of the application of different contact force laws was studied. Moreover, the influence of the geometric and material properties on the dynamic response of the knee joint model was investigated. In a broad sense, the proposed methodologies demonstrated to be suitable for the analysis of the dynamic behavior of multibody models with contact, especially those biological systems such as the knee joint that involve complex geometries, a large range of motion and high dynamic loads.Nesta tese é proposta uma abordagem genérica para a análise dinâmica de sistemas de corpos múltiplos com contacto, dando um especial enfoque ao contacto articular no joelho humano. No âmbito da dinâmica de sistemas de corpos múltiplos são apresentadas duas metodologias, bidimensional e tridimensional, para a modelação do contacto no joelho usando coordenadas cartesianas generalizadas. O desenvolvimento do modelo bidimensional do joelho engloba quatro etapas: (i) representação geométrica dos perfis de contacto por meio de técnicas de ajuste de curva com base em funções de interpolação por splines, (ii) localização dos pontos de contacto e avaliação da indentação de contacto, (iii) cálculo das forças de contacto usando uma lei constitutiva apropriada, (iv) descrição do comportamento dos ligamentos através de uma relação quadrática de tensão-deformação. O movimento da tíbia em relação ao fémur é modelado como uma acção combinada entre os ligamentos do joelho e os potenciais contactos entre os ossos. As forças de contacto, juntamente com as forças produzidas pelos ligamentos, são introduzidas nas equações de movimento de Newton-Euler como forças externas generalizadas. Na metodologia tridimensional, as superfícies de contacto são descritas por meio de nuvens de pontos extraídas de representações paramétricas. No âmbito da formulação tridimensional é apresentada uma unidade de pré-processamento. Este pré-processador permite uma redução significativa da quantidade de memória necessária para o armazenamento de dados e, desta forma, melhora a eficiência computacional do algoritmo de deteção de contacto. Com o objetivo de validar as metodologias propostas, realizaram-se várias simulações computacionais. Os comportamentos do modelo bidimensional do joelho resultantes da aplicação de diferentes leis de força de contacto foram estudados. A influência das propriedades geométricas e de material na resposta dinâmica do modelo bidimensional do joelho foi investigada. De uma forma geral, as metodologias propostas demonstraram ser adequadas para a análise do comportamento dinâmico de modelos de corpos múltiplos com contacto, especialmente sistema biológicos, como o joelho humano, que envolvem geometrias complexas, uma grande amplitude de movimentos e elevadas cargas dinâmicas

Parental Acceptance, Parental Stress, and Quality of Life: A study with parents of ADHD children

Adapting to a child with attention deficit hyperactivity disorder (ADHD) represents a great challenge for any family, and especially for the parents. Considering the psychological and behavioral issues inherent to this disorder, it’s no easy task to promote the child’s development, in a supportive way, while at the same time ensuring that it is well adjusted to all social contexts. More difficult yet is to achieve this while maintaining high quality of interpersonal relations and psychological health in the family. In this context, our research’s objectives were to assess and analyze possible connections between the perception of parental acceptance and rejection, parental stress and quality of family life, in families with children with ADHD. To achieve our goals we applied the Parental Acceptance-Rejection Questionnaire (PARQ, Rohner, 2005), the Quality of Life Scale (QOL, Barnes & Olson, 1982), and the Parental Stress Scale (PSS, Mixão, Leal & Maroco, 2007) to a sample of 57 Portuguese parents, both fathers and mothers, of, at least, one child diagnosed with ADHD. Our results show that parents of children with ADHD perceive themselves as accepting of their children, and the majority present low levels of parental stress. Also, we found that the more stressed parents feel about parenting, the less accepting they perceive themselves to be, as well as having lower levels of quality of life. These results leave interesting pointers for future research andintervention, suggesting the importance of helping parents of ADHD children to deal with stress as it seems to have an important role on key dimensions of family functioning and consequently on children’s socio-emotional adjustment and development

The Use of Pricing Tools to Leverage the Business Partners’ Profitability

The profitability set per customer of a given organization implies several challenges, from the calculation of the net pricing to the development of a cost allocation system within the company's processes. Thus, the work proposed aims at exploring the potential of a customer evaluation methodology, using pricing techniques as a supporting tool, where the analysis of the customer clusters profitability will be done, in order to identify profitability patterns, according to the characteristics of the relationship between the customer and the company, including the customer's supply chain role, the dimension and the potential of the business under study, the types of business relationships that are established, as well as the relative effects of each cluster own characteristics in the overall business relationship. After developing the methodology, the customer profitability will be analyzed and recommendations will be set, highlighting and quantifying the possible improvements in the contribution, under leveraging techniques by the average and sensitivity analysis simulations. These insights will support the companies in their pricing decisions also as shifting their focus towards attracting and retaining the customers from the more profitable clusters

Interbank Linkages and Contagion Risk in the Portuguese Banking System

Mestrado em Economia Monetária e FinanceiraInterbank money markets play a fundamental role in financial systems, since they allow for the redistribution of liquidity between financial institutions. However, they can also be a channel through which problems in one institution can spread to the remaining ones. In particular, the potential for contagion stemming from interbank money markets is closely related with the pattern of interbank lending relationships. In this study, we characterize the Portuguese overnight interbank money market between 1999 and 2009 and analyze its inherent potential for contagion, based on bilateral interbank exposures obtained from the application of Furfine's procedure to settlement data from the Portuguese TARGET component. We conclude that: (i) the Portuguese overnight interbank money market is ruled out by a multiple money center structure, where some banks have, simultaneously, an important role as lenders as well as borrowers; (ii) although unlikely, the failure of one institution can have contagion effects, pushing-others into failure. However, even under the most extreme assumptions, institutions that fail by contagion represent less than 10 per cent of the total banking system assets. On the other hand, even if there are no defaults due to contagion, a foreign bank failure can have non-negligible knock-on effects under national banks. Yet, overnight interbank lending relationships do not generally represent a major threat to the stability of the Portuguese financial system.O mercado monetário interbancário desempenha um papel fundamental no sistema financeiro, permitindo a redistribuição de liquidez entre as instituições financeiras. Porém, pode representar igualmente um canal para a propagação de problemas entre instituições. Em particular, o potencial de contágio existente no mercado interbancário está intimamente relacionado com a estrutura das relações estabelecidas através dos empréstimos interbancários. O presente estudo caracteriza o mercado monetário interbancário overnight português, entre 1999 e 2009, e analisa o potencial de contágio inerente ao mesmo, com base nas exposições interbancárias bilaterais obtidas através da aplicação do procedimento de Furfine aos dados sobre as transacções liquidadas na componente portuguesa do TARGET. É possível concluir que: (i) o mercado monetário interbancário overnight português assenta numa estrutura do tipo "multiple money center", sendo que alguns bancos desempenham um papel fundamental quer como financiadores, quer como mutuários; (ii) apesar de improvável, a falência de uma das instituições participantes no mercado pode ter efeitos de contágio, conduzindo à falência de outras instituições. No entanto, mesmo com pressupostos extremos, as instituições que poderiam falir por contágio representam menos de 10 por cento do activo total do sistema bancário. Por outro lado, mesmo não ocorrendo falências por contágio, a falência de um banco estrangeiro pode ter efeitos não negligenciáveis sobre os bancos nacionais. Não obstante, de uma forma geral, os empréstimos interbancários overnight não representam uma ameaça significativa à estabilidade do sistema financeiro português