Browsing by Issue Date, starting with "2024-01-30"
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- Tourism demand forecasting in Portugal's municipalities : an explainable machine learning approachPublication . Neves, Catarina; Guedes, AnaIn recent decades, the tourism industry has experienced remarkable growth, making it essential to provide accurate forecasts of tourism demand for the efficient allocation of resources and continued growth of the industry. This thesis presents a machine learning approach to forecast tourism demand in Portugal. However, forecasting in the tourism sector faces a challenge: compromising the balance between model accuracy and interpretability. While some highly accurate models lack transparency, making them difficult to understand, this study addresses this concern using the Tree SHAP method. By identifying the contributions of the features, this approach offers a globally interpretable model, increasing the reliability of tourism demand forecasts. This thesis aims to answer: 1) What are the tourism demand trends in Portugal?; 2) What are the key features that most significantly influence tourism demand for different tourist accommodations in Portugal's municipalities?; 3) How to trigger valuable insights in tourism demand forecasting models via the application of explainability strategies? For this purpose, non-public data from Turismo de Portugal and additional variables, such as population, are used to train an XGBoost model. The main predictors of demand in Portugal were revealed, including summer, population, and number of beds. This study has practical implications for policymakers and management teams in the marketing and tourism sectors, providing valuable information for decision-making in the sector.
- Do direito de retenção atribuído ao promitente-comprador no âmbito do processo de insolvência do promitente-vendedorPublication . Margarido, Paula Cristina Baptista; Ribeiro, Maria de Fátima SilvaO Supremo Tribunal de Justiça, e pelos Acórdãos Uniformizadores de Jurisprudência nºs 4/14 e 4/19 proferidos em sede de processo de insolvência, tem efetuado uma interpretação restritiva da alínea f) do n.º 1 do art. 755º do CC, considerando que aquele direito de garantia, e até em face da prevalência face à hipoteca (ainda que anteriormente registada) apenas se aplica ao promitente beneficiário da promessa que é consumidor e nos casos em que o imóvel, objeto da traditio, se destina à habitação ou a uso particular. Logo, no âmbito dos processos de insolvência do promitente-alienante, entende o Supremo Tribunal de Justiça que nas promessas obrigacionais e com traditio, em que o imóvel se destina à habitação, o beneficiário consumidor da dita promessa, e desde que verificados os respetivos pressupostos, tem o seu crédito garantido pelo direito de retenção, prevalecendo este sobre a hipoteca. A verdade é que não parece legalmente admissível uma interpretação restritiva, da alínea f) do n.º 1 do art.755 do CC, pois não tem respaldo na lei. E o direito de retenção ali previsto não será de aplicar ao processo insolvencial, porquanto este contempla um regime imperativo que não prevê a aplicação daquele preceito e consequentemente da atribuição de tal direito de garantia. Logo, o crédito do dito beneficiário da promessa será classificado como comum e já não como crédito garantido. A diferenciação de regimes tem levado o Supremo Tribunal de Justiça a corrigir interpretativamente a lei, ainda que contra legem. Entende-se que somente uma alteração legislativa ao art. 106º do Código de Insolvência que venha a conceder ao beneficiário da promessa, ainda que com eficácia meramente obrigacional e em que tenha acontecido a traditio, o direito de retenção previsto na alínea f) do n.º 1 do art. 755º do CC, sem que se admita a interpretação restritiva, permitirá a adequada proteção legal deste beneficiário.
- Target Corporation, Inc. equity valuationPublication . Monteiro, Catarina Vinhas; Martins, José Carlos TudelaThe main objective of this dissertation is to carry out the equity valuation of Target Corporation, a retail company based in the United States of America that belongs to the S&P index 500, in order to determine the price per share. Firstly, an industry analysis in which the company operates was carried out, thus, the North American market was characterized, the main competitors identified, as well as the opportunities and challenges of the sector.It was also analyzed the global economic context and its impact on the retail sector. On the other hand, the financial history of some company indicators was analyzed in order to deepen knowledge about it and choose the most suitable methods. The main method used was Discounted Cash Flow (DCF), having been determined an intrinsic value of $124.64. Comparing this value with the market value, $129.94 (16𝑡ℎ November 2023), a HOLD recommendation on the shares of Target Corporation share’s was issued. A relative assessment using multiples was performed, however it was discarded due to the difficulty in identifying a peer group that could be compare to Target Corporation.
- Machine learning algorithms for predicting EQ-5D full health state in systemic lupus erythematosusPublication . Botto, João Ricardo da Costa Monteiro; Parodis, IoannisObjectives: To determine factors associated with EQ-5D full health state (FHS) in systemic lupus erythematosus (SLE) before and after a trial intervention, resorting to machine learning algorithms. Methods: We conducted a post-hoc analysis of data from two phase III clinical trials of belimumab (BLISS-52, BLISS-76). Demographic, laboratory, and clinical features were retrieved, and the Monte Carlo Feature Selection algorithm was employed, further refined upon consideration of collinearity and clinical relevance/expertise. The models used were support vector machine with radial basis function kernel (SVMRadial), least absolute shrinkage and selection operator (LASSO), neural network (NNet), and logistic regression (LR). Results: In a cohort of 1642 SLE patients, 12.9% reported FHS at baseline and 23.1% at week 52. Selected features were age, sex, Asian ancestry, baseline clinical Systemic Lupus Erythematosus Disease Activity Index-2000, Safety of Estrogens in Lupus National Assessment-SLEDAI Physician Global Assessment, and urine protein/creatinine ratio (UPCR), and baseline EQ-5D utility index score (week-52 models only). The models predicting FHS demonstrated comparable performance at baseline and week 52, where for baseline a maximum area under the curve of 0.73 was seen for the LASSO and LR models, versus a 0.77 maximum for the week-52 LASSO and NNet models. Particularly high for all models was the negative predictive value (0.88–0.94). Calibration showed marginal improvement in week-52 models. Conclusion: Machine learning identified older age, female sex, non-Asian ancestry, high disease activity, and low UPCR to be associated with a lack of FHS experience in SLE patients at baseline and week 52. Baseline EQ-5D utility index constituted the most informative feature for predicting FHS experience at week 52.
- Organizational purpose and meaningful work : the role of work centrality and purpose statementsPublication . Offinger, Lenja Eleanor; Cavicchini, AndreaThis study explores the relationships between organizational purpose, work centrality, purpose statement content, and work meaningfulness. The study uses a mixed-methods approach that includes primary data in the form of eight interviews and surveys as well as related theories as secondary data included in the literature review. Quantitative results reveal a partial mediation effect of work centrality and a positive relationship between perceived organizational purpose and meaningful work. Furthermore, meaningful work is directly influenced by organizational purpose, whereas work meaningfulness has a weak indirect effect, suggesting that other influential factors are involved. Qualitative insights offer diverse employee viewpoints regarding the purpose of the organization. The impact of purpose on job satisfaction and the importance of sustainability was acknowledged by the interviewees, however, concerns arose regarding operational alignment with the purpose statement. The purpose statement was perceived as directing daily activities; however, it did not always impact day-to-day operations. The study also investigates whether the relationship between meaningful work and perceived purpose is mediated by the purpose statement’s content. The results point to a possible role for content even though it has no significant effect on the relationship between meaningful work and perceived purpose, suggesting the existence of unmeasured variables. Overall, this study adds to the understanding of the ways in which work centrality, organizational purpose, and purpose statement content interact to create meaningful work experiences. These complex results help clarify the intricate dynamics of organizational purpose in creating meaningful work.
- A insolvência culposa e a exoneração do passivo restantePublication . Costa, Ana Filipa Silva de Oliveira e; Campos, Maria Isabel Helbling MenéresA presente dissertação versa sobre duas temáticas: a insolvência culposa e a exoneração do passivo restante. Encetamos o estudo com a insolvência culposa e por que motivos é que esta, estando revestida de culpa, impede que a exoneração do passivo restante seja passível de ser aplicada. Ultimamos, precisamente, com uma articulação entre os institutos. Analisaremos com mais pormenor qual a origem dos regimes, os fundamentos e pressupostos de cada um, o seu procedimento, quais os seus efeitos, se se relacionam, ou se, pelo contrário, se tratam de regimes controversos.
- A impugnação pauliana e a insolvênciaPublication . Andrade, Mónica Solange Guerra Ventura; Campos, Maria Isabel Helbling MenéresNo presente trabalho abordamos a temática da utilidade da impugnação pauliana no âmbito do direito de insolvência. Os efeitos marcadamente pessoais da impugnação pauliana, estabelecida enquanto garantia de conservação patrimonial em favor dos credores, colidem com os princípios da universalidade e da igualdade dos credores que regem o processo de insolvência. Desta forma, a jurisprudência e doutrina maioritárias entendem que os efeitos da impugnação pauliana só deverão ser acolhidos no processo de insolvência no caso de não haver a resolução dos atos praticados pelo devedor em benefício da massa insolvente. Através da análise de ambos os regimes, abordaremos os principais aspetos contraditórios quanto à utilidade dos efeitos da procedência impugnação pauliana perante a insolvência do devedor.
- Impact accounting : developing a first approach for monetizing the impact of corporate in-kind donations on the communityPublication . Mößle, Katharina; Cruz, Nuno Moreira daThe thesis aims to develop a possible approach for Sonae MC to monetize the impact of corporate in-kind donations on the community. The current accounting system lacks a comprehensive understanding of a company's value creation, as it cannot incorporate social and environmental impact. This also applies to in-kind donations. Only the impact of corporate in-kind donations on the corporation’s financial situation is considered in the accounts. The literature lacks information on the impact created through in-kind donations on the community. Existing research focuses on the impact of in-kind donations on the corporation’s financial performance. The findings indicate that corporations are currently measuring the impact of in-kind donations on the community in terms of inputs (monetary value of in-kind donations) and/or outputs (number of institutions reached), based on different calculations, and monetizing procedures. Measuring the impact of in-kind donations on the community turns out to be difficult and very complex. As a first approach to monetizing the impact of in-kind donations on the community, the thesis proposes to determine a market value for corporate in-kind donations in a standardized way. The market value is suggested to be determined based on the average retail price, which makes it possible to value in-kind donations independently of a company's price or cost structure.
- Equity valuation Philip Morris International Inc.Publication . Côdea, Francisco; Martins, TudelaThe year 2022 brought unprecedented economic challenges, with inflation rates reminiscent of the 1980s and a surge in interest rates in response. This volatile landscape posed significant obstacles for companies like Philip Morris International, resulting in dwindling sales volumes and escalating production costs, ultimately reflected in a 0.6% decline in net income for the year. Amidst these dynamics, this thesis delves into the valuation of PMI, employing diverse valuation models that consider geopolitical tensions, market expansions, and evolving consumer preferences. The study utilized discounted cash flow and relative valuation models, subjecting potential scenarios to Monte Carlo and sensitivity analyses. These analyses rigorously tested the valuation's sensitivity to variations in the discount rate and growth rate (by 0.1 percentage points), examining the share price's responsiveness to changes in growth, corporate tax rate, and key macroeconomic factors, such as the risk-free rate, country risk premium, and cost of traded debt. The resulting estimated share price of $93.06 reflects a 1.35% decline from November 24, 2023, value of $94.34, supporting the thesis's recommendation to Hold PMI shares. Furthermore, a comparative assessment with Barclays' valuation reveals contrasting forecasts for PMI, highlighting the divergence of perspectives on the company's future trajectory. This comprehensive evaluation aims to provide nuanced insights into PMI's valuation landscape within a complex global economic paradigm, informing potential investment decisions.
- Short-communication: study of fatty acid metabolites in microbial conjugated fatty acids-enrichment of milk and discovery of additional undescribed conjugated linolenic acid isomersPublication . Fontes, Ana Luiza; Neves, Bruna; Conde, Tiago; Couto, Daniela; Pimentel, Lígia Leão; Rodríguez-Alcalá, Luis Miguel; Domingues, M. Rosário; Gomes, Ana MariaMicrobially enriched food in conjugated linoleic (CLA) and conjugated linolenic (CLNA) acids is intensively studied nowadays. The conversion of linoleic (LA) and α-linolenic acids (α-LNA) into these compounds may involve different fatty acid (FA) intermediates. This research aimed to investigate potential FA byproducts in milk during microbial CLA/CLNA-enrichment using Bifidobacterium breve DSM 20091. Milk fermented with pure α-LNA showed a decrease in free myristic acid, while pure LA led to an increase in free stearic acid. No additional FA compounds were found alongside CLA/CLNA isomers. The strain produced several CLA isomers from LA, but only when administered alone. Nonetheless, when α-LNA was assayed, additional CLNA isomers, never reported before for bifidobacteria, were observed. In conclusion, except for stearic acid in the presence of LA, no side-FA metabolites were released during milk microbial CLA/CLNA-enrichment. Results suggest either CLA/CLNA production occurs in one single-step or intermediates biotransformation is very fast.
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