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- ItemImputation of Data Missing Not at Random: artificial generationand benchmark analysis(Elsevier, 2024-09-01) Pereira, Ricardo Cardoso; Abreu, Pedro Henriques; Rodrigues, Pedro Pereira; Figueiredo, Mário A. T.Experimental assessment of different missing data imputation methods often compute error rates between the original values and the estimated ones. This experimental setup relies on complete datasets that are injected with missing values. The injection process is straightforward for the Missing Completely At Random and Missing At Random mechanisms; however, the Missing Not At Random mechanism poses a major challenge, since the available artificial generation strategies are limited. Furthermore, the studies focused on this latter mechanism tend to disregard a comprehensive baseline of state-of-the-art imputation methods. In this work, both challenges are addressed: four new Missing Not At Random generation strategies are introduced and a benchmark study is conducted to compare six imputation methods in an experimental setup that covers 10 datasets and five missingness levels (10% to 80%). The overall findings are that, for most missing rates and datasets, the best imputation method to deal with Missing Not At Random values is the Multiple Imputation by Chained Equations, whereas for higher missingness rates autoencoders show promising results.
- ItemA Perspective on the Missing at Random Problem: synthetic generation and benchmark analysis(IEEE - Institute of Electrical and Electronics Engineers, 2024-11-12) Cabrera-Sánchez, Juan Francisco; Pereira, Ricardo Cardoso; Abreu, Pedro Henriques; Silva-Ramírez, Esther LydiaProgressively more advanced and complex models are proposed to address problems related to computer vision, forecasting, Internet of Things, Big Data and so on. However, these disciplines require preprocessing steps to obtain meaningful results. One of the most common problems addressed in this stage is the presence of missing values. Understanding the reason why missingness occurs helps to select data imputation methods that are more adequate to complete these missing values. Missing at Random synthetic generation presents challenges such as achieving extreme missingness rates and preserving the consistency of the mechanism. To address these shortcomings, three new methods that generate synthetic missingness under the Missing at Random mechanism are proposed in this work and compared to a baseline model. This comparison considers a benchmark covering 33 data sets and five missingness rates (10%,20%,40%,60%,80%). Seven data imputation methods are compared to evaluate the proposals, ranging from traditional methods to deep learning methods. The results demonstrate that the proposals are aligned with the baseline method in terms of the performance and ranking of data imputation methods. Thus, three new feasible and consistent alternatives for synthetic missingness generation under Missing at Random are presented.
- ItemO Mundo em Casa: o sucesso da televisão por cabo na era da internet(Asociación Internacional de Psicología Evolutiva y Educativa de la Infancia y de la Adolescencia, Mayores y Discapacidad (INFAD), 2015-07-15) Figueiredo, SofiaEste artigo é baseado num estudo longitudinal, entre 2005 e 2015, acerca do consumo da TV por cabo de famílias, numa área urbana do Norte de Portugal. Na última década, a televisão por cabo tem ganho dimensão e relevância, em paralelo com o crescimento do consumo da Internet, dois ícones da cultura digital de hoje. Em ambos os casos, a televisão e a Internet tendem a ser práticas crescentemente individualizadas e personalizadas, expressando identidade, preferências e diferença, e não mais rituais familiares coletivos. Ao contrário, porém, das perspetivas sobre o futuro da televisão, segundo as quais a expansão do consumo da televisão através da própria Internet, em casa e fora de casa, tende a liquidar a televisão como nós a conhecemos, a questão é que a cultura da televisão muda conforme muda a sociedade e a família, de modo que ver televisão sentado diante do aparelho continua ainda a ser uma marca distintiva do continuum cultural entre a casa e o mundo. | This article is based on a longitudinal study, between 2005 and 2015, on households cable television consumption in an urban area of northern Portugal. During the last decade, cable television has gained dimension and relevance in parallel with the growth of Internet, two icons of today’s digital culture. In both cases, television and Internet consumption at home tends to be increasingly individualized and personalized practices, expressing identity, preferences and difference, and no longer collective family rituals. However, contrary to the perspectives on the future of television, according to which the expansion of streaming television through the Internet, both at home and away from home, tends to liquidate television as we know it, the question is that television culture changes as society and family change, so that to watch TV sitting in front of the television set still continues to be, in the age of Internet, a hallmark of the cultural continuum between home and the world.
- ItemModeling Inter‑organizational Business Process Governance in the Age of Collaborative Networks(Springer, 2024-10-04) Ribeiro, Vítor; Barata, João; Cunha, Paulo Rupino daCollaborative networks require inter-organizational business process governance (IO-BPG) mechanisms to define ownership over shared resources and activities, accountability over operations, inter-organizational roles and responsibilities, and strategic partner alignment. We developed an IO-BPG modeling approach aiming to incorporate (1) IT governance activities (e.g., IT performance measurement), (2) data governance activities (e.g., data strategy management), and (3) “shadow” parallel governance-related operations. Resulting from a design science research project, our contributions include the building blocks (domain attributes, ontology, and requirements) of a novel BPMN extension, its demonstration in logistics operations, its evaluation, and design principles to guide IO-BPG modeling. Suggestions for the development and evaluation of future BPMN extensions are also highlighted based on the lessons learned in this project. For practitioners, our contribution can improve accountability reports over data assets and operations, identify dataset ownership, assist in the coordination of governance activities in networked businesses, and comply with regulations and strategic partnership agreements.
- ItemDigital Transition and Home Education: challenges and opportunities for psychological intervention(Conference INTED24, 2024-03-04) Oliveira, Francisca; Castanheira, Gabriela; Oliveira, Rui; Cunha, Luís; Costa-Lobo, CristinaThe 21st century is being marked by a series of significant changes in educational practices that are having a profound impact on psychological intervention. These changes are driving the genesis of an innovative era of personalized, digital, and accessible education. Individualization is the tendency to adapt teaching to the individual needs of students. Artificial intelligence has the potential to transform education and can be used to personalize teaching, automate routine tasks, and assess student performance. It is true that there are obvious constraints and that it is a challenge to carry out psychological intervention in a “distance” school context, Psychologists must maintain coordinated and shared planning with the other educational actors, the emphasis on preventive and multilevel interventions and management of priorities that respect their technical and scientific autonomy. The Psychologist's support is particularly important in situations that involve (i) entry into schooling (including the analysis of requests for postponement/anticipation), (ii) cycle transition, (iii) change of educational establishment; or (iv) access and entry into Higher Education, especially if we consider that after the situation of isolation at home, the return to school/higher education institution may occur through the abrupt interruption of academic activities and attendance at an educational establishment only to, months later, return to a different space and educational establishment, often unaccompanied by their colleagues and friends. It will be important, for example, to promote literacy about transition and adaptation to change; create a dedicated space, inside or outside distance learning activities, to work on this life topic with students and families who are in this situation; build and share other digital or material resources; or intervention from the areas of action already mentioned. The guiding question of this study was: What are the challenges and what are the opportunities of the digital transition for home education? The aim of this work was to investigate how the digital transition can affect home education and identify the trends and challenges of home education in the context of the digital transition. The research was carried out in four databases with combinations of the words digital transition, home education, digital technologies, curriculum, regulation, psychological intervention. We consider 25 articles published in international scientific journals between January 2007 and September 2022, two books and two documents of a normative nature, authored by the American government. All articles met the inclusion criteria. The documents were described, and the content was systematized in a meta-synthesis. The study detailed here carries out the analysis of how the adoption of digital technologies in schools and families can have an impact on the way in which home education is carried out, identifying the challenges and opportunities of this transition, such as the need for training parents and educators, the adequacy of curricula and the regulation of home education and investigates how home education is evolving in the context of the digital transition. Implications for psychological intervention are presented.