Papers by domingos martinho
Economies
The main goal of this research is to study the impact of uncertainty on export performance, from ... more The main goal of this research is to study the impact of uncertainty on export performance, from a resource-based perspective. Despite the ample research on how economies behave during periods of high uncertainty, there is still a poor understanding of how this affects smaller sectors, particularly the most exposed to global competition. In this paper, we perform an evaluation of export performance for the Portuguese pharmaceuticals sector (PPI), before and after a period of considerable uncertainty. This study’s results show strong incremental performance gains, during this period. It also confirmed the importance of marketing capabilities, innovation and networking resources in developing international businesses.
Electronics
Dropout prediction is a problem that must be addressed in various organizations, as retaining cus... more Dropout prediction is a problem that must be addressed in various organizations, as retaining customers is generally more profitable than attracting them. Existing approaches address the problem considering a dependent variable representing dropout or non-dropout, without considering the dynamic perspetive that the dropout risk changes over time. To solve this problem, we explore the use of random survival forests combined with clusters, in order to evaluate whether the prediction performance improves. The model performance was determined using the concordance probability, Brier Score and the error in the prediction considering 5200 customers of a Health Club. Our results show that the prediction performance in the survival models increased substantially in the models using clusters rather than that without clusters, with a statistically significant difference between the models. The model using a hybrid approach improved the accuracy of the survival model, providing support to deve...
Este trabalho teve por objetivo apresentar e testar um modelo de aceitação do ensino online pelos... more Este trabalho teve por objetivo apresentar e testar um modelo de aceitação do ensino online pelos estudantes do ensino presencial. Participaram na investigação, desenvolvida através da técnica de inquérito por questionário, 732 estudantes que frequentavam cursos de 1º ciclo (licenciatura) em 11 instituições de ensino superior (IES) privadas portuguesas. Construiu-se um modelo de aceitação do ensino online (MAEO) tendo por base quatro dimensões: Utilidade percebida, Atitude, Experiência tecnológica e Intenção de uso. Os resultados obtidos, com recurso à modelação de equações estruturais, revelaram que a Utilidade percebida e a Atitude constituem fatores de predição da Intenção de uso do ensino online e que a Utilidade percebida tem efeito sobre a Atitude. Concluiu-se ainda que a Experiência tecnológica não tem efeito, com significado estatístico, sobre a Utilidade percebida nem sobre a Atitude.info:eu-repo/semantics/publishedVersio
In the ornamental stone industry, improving production processes is a constant challenge for mana... more In the ornamental stone industry, improving production processes is a constant challenge for managers looking for solutions that improve the competitiveness of the companies. The management of cutting and computerized cut command machine tools is one of the areas where this improvement in management processes can have a positive effect on the competitiveness and productivity of companies. With this purpose, a model based on business intelligence methodologies was developed to systematize and automate the management process. The proposed model consists of the following layers: acquisition, extract, transform and load, storage and access and analysis. The acquisition layer consists of the interface with data available in various formats. The extract, transform and load process aims to extract data from these repositories and load them into a data warehouse. While the access and analysis phase is based on the use of software tools with graphical user interface with advanced analysis re...
Wine companies operate in a very competitive environment in which they must provide better-custom... more Wine companies operate in a very competitive environment in which they must provide better-customised services and products to survive and gain advantage. The high customer turnover rate is a problem for these companies. This work aims to provide wine companies with new knowledge about customers that help to retain the existing ones. The study applies a collected dataset from a transaction database in a medium-sized ortuguese wine company to determinate: (1) customer lifetime value; (2) cluster customer value as output (customer loyalty). The measurement of the customer lifetime value (CLV) was analysed using the Pareto/NBD model and gamma-gamma model. Clustering techniques are employed to segment customers according to Recency, Frequency, and Monetary (RFM) values. Study findings show that exists three clusters with different interest to the marketing strategies, identifying the high-value customers, to target using marketing to increase their lifetime value effectively. The implic...
Com este estudo pretende-se contribuir para a definição de um modelo de aceitação do ensino pós g... more Com este estudo pretende-se contribuir para a definição de um modelo de aceitação do ensino pós graduado online. O trabalho de campo foi desenvolvido durante o primeiro trimestre de 2017 junto dos estudantes que frequentaram formação pós-graduada online numa instituição de ensino superior nos últimos quatro anos letivos. A partir de estudos anteriores sobre esta temática construiu-se um modelo de aceitação do ensino online (MAEO) tendo por base cinco dimensões: Utilidade percebida, Atitude, Facilidade de uso, Experiência tecnológica e Intenção de uso. Os resultados obtidos, com recurso à modelação de equações estruturais, revelaram que a Atitude em relação ao ensino online e a perceção de Utilidade constituem fatores de predição da Intenção de uso. Verificou-se ainda que a Facilidade de uso induz um efeito direto e indireto sobre a Intenção de uso e que a experiência tecnológica tem efeito, com significado estatístico, sobre a Facilidade de uso e em menor grau sobre a Utilidade perc...
A investigação sobre os fatores que levam os candidatos a optar por ensino online pode fornecer i... more A investigação sobre os fatores que levam os candidatos a optar por ensino online pode fornecer informação muito relevante para os decisores das IES ajustarem essas ofertas aos interesses e necessidades dos estudantes. Com essa finalidade desenvolveu-se uma investigação que envolveu os estudantes que frequentaram, formação pós graduada numa instituição de ensino superior em regime totalmente online nos últimos quatro anos letivos. Os resultados obtidos permitem concluir que a maioria dos inquiridos prefere o ensino totalmente online e que a sua decisão no momento de optarem por este tipo de cursos, é influenciada, sobretudo, pela flexibilidade na gestão do tempo, não serem necessárias deslocações à escola e pelo interesse no currículo do curso. Constatou-se ainda que aspetos tais como: curiosidade em saber como funciona o ensino online e a possibilidade de trabalhar com professores ou estudantes de outras escolas não são considerados relevantes no momento de decidir sobre a frequênc...
Revista Paidéi@ - Revista Científica de Educação a Distância, Jun 30, 2015
IEEE Access, 2022
Dropout prediction is a problem that is being addressed with machine learning algorithms; thus, a... more Dropout prediction is a problem that is being addressed with machine learning algorithms; thus, appropriate approaches to address the dropout rate are needed. The selection of an algorithm to predict the dropout rate is only one problem to be addressed. Other aspects should also be considered, such as which features should be selected and how to measure accuracy while considering whether the features are appropriate according to the business context in which they are employed. To solve these questions, the goal of this paper is to develop a systematic literature review to evaluate the development of existing studies and to predict the dropout rate in contractual settings using machine learning to identify current trends and research opportunities. The results of this study identify trends in the use of machine learning algorithms in different business areas and in the adoption of machine learning algorithms, including which metrics are being adopted and what features are being applied. Finally, some research opportunities and gaps that could be explored in future research are presented.
International Journal of Service Science, Management, Engineering, and Technology, 2022
One of the methods which could improve the safety performance of construction organizations is th... more One of the methods which could improve the safety performance of construction organizations is the safety climate approach which is helpful to know the existing maturity level of the safety climate and to develop plans to achieve the required level of maturity. Most of the existing safety climate tools were developed considering different industries in developed countries while construction was based only on few tools. Construction projects in the Gulf Cooperation Council (GCC) member countries are at a peak. This article, therefore, attempts to develop a safety climate assessment tool for the Omani construction industry. A mixed research method consisting of systematic review (N = 32), structured questionnaire (N = 102) and email interview (N = 19) was adopted in this research. An assessment tool that has seven factors and 62 simple questions that the participants have to answer on a Likert scale of 1 to 5 is finally developed.
2018 13th Iberian Conference on Information Systems and Technologies (CISTI), 2018
Resumo-A previsão de vendas constitui um fator fundamental para o planeamento da atividade das em... more Resumo-A previsão de vendas constitui um fator fundamental para o planeamento da atividade das empresas fornecendo indicadores importantes para o suporte das decisões dos gestores. Este estudo visa explorar o potencial dos algoritmos para previsões baseado em time series, numa empresa da área das TI. A previsão foi realizada com base nos dados de faturação da empresa durante 192 meses de atividade. A análise dos dados baseou-se na abordagem CRoss Industry Standard Process for Data Mining e para o tratamento recorreu-se ao Anaconda IPython e Pandas. A previsão foi realizada em R com três modelos: Exponencial Smoothing (Holt-Winters), autoregressive integrated moving average (ARIMA) e artificial neural networks (ANN). A comparação do desempenho de cada um dos métodos mostra que o modelo baseado em artificial neural networks tem uma maior exatidão na previsão. Estes resultados carecem de um aprofundamento do estudo alargando o universo dos contextos estudados, contudo a simplicidade na aplicação do modelo baseado artificial neural networks, possibilita a sua utilização em aplicações informáticas utilizadas pelas empresas sem necessidade conhecimentos específicos, fornecendo um instrumento fiável que possibilite o apoio à tomada de decisão por parte dos gestores. Palavras Chave-algoritmos; redes neuronais; suporte à decisão; time series.
Atualmente vem-se assistindo a um aumento dos servicos de entregas de mercadorias a clientes que ... more Atualmente vem-se assistindo a um aumento dos servicos de entregas de mercadorias a clientes que sao oferecidos pelas organizacoes de diversos setores de modo a aumentar a oferta dos seus produtos e servicos e a combater a concorrencia no mercado. O consumo de tempo, atrasos devido a trânsito e outras circunstâncias fazem tambem com que este tipo de servicos aumente os seus custos de forma muito significativa. Surge assim a oportunidade para o desenvolvimento de solucoes que permitam a otimizacao das rotas de modo a minimizar os custos inerentes ao processo o que tem levado muitos investigadores a estudarem o problema e ao surgimento no mercado de diversas aplicacoes que pretendem ajudar as empresas nesse tipo de servicos, fazendo uso de algoritmos desenvolvidos para a otimizacao de rotas. Neste contexto este trabalho tem como objetivo a criacao de uma plataforma que permita a insercao de encomendas de clientes e posteriormente otimizar as rotas para as entregas associadas a cada ve...
A previsao do tempo de permanencia por parte dos utentes de lares, baseada na analise dos dados e... more A previsao do tempo de permanencia por parte dos utentes de lares, baseada na analise dos dados existentes, constitui um indicador da maior importância para os gestores deste tipo de equipamentos ajudando-os a planear os recursos necessarios. Neste estudo desenvolveu-se uma analise para determinar o tempo de permanencia de um idoso num lar e quais sao as variaveis que influenciam esse tempo de permanencia. Os dados foram analisados tendo por base o modelo de regressao de Cox onde se verificou que as variaveis faturacao acumulada, Idade e distância da residencia ao lar tem impacto no tempo de permanencia. Na aplicacao do teste log-rank encontramos diferencas na sobrevivencia nas variaveis faturacao acumulada e idade. Os resultados obtidos podem ser uteis para avaliacao do tempo que decorre ate ao abandono e dessa forma permitir planear os recursos necessarios para acompanhar os utentes dos lares.
Communications in Computer and Information Science, 2021
International Journal of Service Science, Management, Engineering, and Technology, 2022
This study integrates the relationship of business ethics in marketing campaigns and the importan... more This study integrates the relationship of business ethics in marketing campaigns and the importance of the repercussion on organizational performance with the aim of creating a guide of business ethics in marketing campaigns for small and medium enterprises (SMEs). This guide allows SMEs to analyse their ethical dimension as well as to raise awareness and instill commercial ethics actions in the marketing campaigns common practice in organisations. The qualitative methodology has been applied and the proposed theoretical model uses a set of dimensions of ethics, commercial ethics, codes of conduct, marketing, and marketing campaigns to analyse the relationship of commercial ethics with marketing campaigns and its influence on organisations. The result demonstrates the influence of commercial ethics on advertising actions, when applied positively, enables and promotes the brand image, thus contributing to the organizational performance.
Proceedings of Sixth International Congress on Information and Communication Technology, 2021
Pharmaceutical industry faces the pressure of a global economy, the loss of value in local market... more Pharmaceutical industry faces the pressure of a global economy, the loss of value in local markets and the highly innovative intensity that characterizes the sector. With this investigation, we intend to carry out the first characterization of the Portuguese pharmaceutical industry. This study aims to identify the determinants of internationalization as levers of sustainability and to establish a pattern that corresponds to better outcomes in pharmaceutical companies’ internationalization ventures. All companies from the Portuguese pharmaceutical export sector, a total of 16 companies, were contacted. Data was collected from a highly representative sample corresponding to 63% of the total. A previous contextualization of the pharmaceutical sector and a bibliographic review were carried out, creating the basics of the empirical framework, a quantitative research. This study revealed a deeply internationalized sector, but the overall results are conditioned by some weaknesses, namely ...
Education Sciences, 2021
Due to the COVID-19 pandemic, higher education institutions with a face-to-face model have found ... more Due to the COVID-19 pandemic, higher education institutions with a face-to-face model have found themselves in the contingency of migrating to online learning. This study explores the perspective of all the lecturers at a Portuguese private higher education institution who were invited to participate, regardless of their research area, in this questionnaire. It aims to propose and test a conceptual model that combines attitudes, preferred activities, and technological experience with the sentiment about the impact of this experience on students’ learning process, on their teaching activity, and on the strategy of higher education institutions. An online questionnaire was conducted to 65 lecturers engaging in emergency online lecturing. The obtained results showed that lecturers reveal a positive attitude towards online lecturing, tend to prefer activities in which they feel most comfortable in face-to-face lecturing, and consider having technological experience useful for online act...
Sustainability, 2020
In a globalization context, underlined by the speed of technological transformation and increasin... more In a globalization context, underlined by the speed of technological transformation and increasingly competitive markets, the perspective of human capital, as an asset of strategic importance, stands out in differentiating human resource practices. Under this reality, the employer branding (EB) concept gains more and more importance as a strategic tool to attract, retain, and involve human capital, given that this has become a source of competitive advantage to companies. Within this context, this study aimed to evaluate the relationship between employer branding strategies implemented by organizations, as well as their impact on the employee’s affective commitment, evident in certain organizational cultures, which are sustained over time. The methodological framework applied to this study is quantitative, and the data collection was carried out with the application of an employer branding and an affective commitment questionnaire. To achieve a good representation of the active popu...
International Journal of Emerging Technologies in Learning (iJET), 2018
A research about factors that lead students to choose online courses, as well as the acceptance o... more A research about factors that lead students to choose online courses, as well as the acceptance of these courses, can provide very relevant information for higher education institutions’ decision makers to amend these offers to students’ interests and needs. An investigation through questionnaire was developed involving students who attended online post-graduate courses. It was intended to know which factors affect students' decision to opt for postgraduate online courses. A model, based on the TAM (Technology Acceptance Model), was tested to find out what factors determine the intention to use online learning. The results shows that most respondents favour online courses and that their decision, when choosing this type of course, is mainly influenced by time management flexibility, avoiding going to school and the course curriculum interest. The test of the model, with structural equations, shows that attitude regarding online courses and perceived usefulness are factors that p...
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Papers by domingos martinho