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Sovereign bond and CDS market contagion: A story from the Eurozone crisis
No full textWe examine the asymmetric and nonlinear nature of the cross- and intra-market linkages of eleven EMU sovereign bond and CDS markets during 2006–2018. By adopting the excess correlation concept of Bekaert et al. (2005) and the local Gaussian correlation approach of Tjøstheim and Hufthammer (2013), we find that contagion phenomena occurred during two major phases. The first, extends from late 2009 to mid 2011 and concerns the outright contagion transmission from EMU South bond markets towards all European CDS markets. The second, is during the revived fears of a Greek exit in November 2011 and is characterized by contagion from (i) CDS spreads in the EMU South towards bond yields in the same bloc and Belgium, and (ii) from Italian and Spanish CDS spreads towards all European CDS spreads. Consistent with their “too big to bail out” status, Italy and Spain emerge as pivotal for the evolution of sovereign credit risk across the Eurozone. Our examination of the relevant mechanisms, highlights the importance of credit risk over liquidity risk, and the containment effect of the naked CDS ban.13710290
Does Lexical Stress Pattern Affect Learning and Producing New Words in Greek for Children With Cochlear Implants?
No full textPurpose: The lexical stress pattern (trochaic vs. iambic) may affect various aspects of word learning and word production in children with cochlear implants (CIs). This study aimed to investigate lexical stress effects in word learning by Greek-speaking children with CIs. Method: A word learning paradigm, consisting of a word production and a word identification task, was used. A test list of eight pairs of disyllabic nonwords with identical phonological composition and contrasting lexical stress (eight trochaic and eight iambic), along with their referent pictured objects, was constructed and administered to 22 Greek-speaking children with CIs (ages 4;6-12;3 [years;months]) with normal nonverbal IQ and to 22 age-matched controls with normal hearing (NH) and no other difficulties. Results: Overall, children with CIs exhibited lower performance than their hearing peers in all word-learning tasks, regardless of lexical stress pattern. Specifically, they identified significantly fewer words and exhibited significantly lower accuracy in word production than those of the controls. In the group with CIs, lexical stress pattern affected their production of words but not their word identification. Children with CIs showed more accurate production of iambic than trochaic words, a fact attributed to better vowel production. Yet, production of stress was less accurate for iambic than for trochaic words. Moreover, stress assignment of iambic words was highly correlated with speech and language tests in children with CIs. Conclusions: Greek children with CIs exhibited lower performance in the wordlearning task administered than children with NH did. In addition, the performance of children with CIs indicated a dissociation between the perception and production mechanisms and revealed complex relations between the segmental and prosodic aspects of words. Preliminary findings suggest that stress assignment in iambic words can serve as an indicator of speech and language growth.6682535256
From Nasser to Arafat and Ibn Salman; the Greek pro-Arabism revisited
No full textThis study revisits the evolution of contemporary Greek–Arab relations from a geopolitical perspective. For a number of reasons – inter alia, her lack of a colonialist past – Greece has been time and again associated with a strong pro-Arab reputation. Greek pro-Arabism survives to this day; however it has undergone dramatic changes in terms of content, rhetoric and objectives. In fact, the once staunchest European supporter of the Palestinian cause and ‘pariahs’ like Qaddafi, Arafat and Hafez al-Asad, is now firmly aligned with Israel and the Gulf monarchies. By adopting a longitudinal approach, this article highlights the drivers and the constraints of the Greek pro-Arab policies diachronically and investigates the current convergence or divergence of interests between Athens and its new Arab friends.481396
Η συμβολή της σημειωτικής στη σύλληψη οντολογίας από κείμενα
No full textThe advent of the digital age has brought significant changes to the daily lives of humanity. Many human activities were redefined in the context of a new, virtual space, the world of the Internet. This networked space, with its innumerable data and abundance of information, is faced with a serious issue, the "information chaos". In short, this issue is closely associated with the correct retrieval of information achieved mechanically. Understanding and describing the real world plays an important role, among many others, in addressing this issue. On the World Wide Web, this process is carried out using digital semantic technologies, such as, for example, ontologies that have undertaken the conceptual description of the world and its representation. Besides, a very great part of knowledge and information is found in texts which become the input corpus for the capture of ontologies. In this context, this paper aims to explore the links that bring together the fields of ontological engineering and (textual) semiotics. The challenge emerging is the adoption of the fundamental principles of structural and interpretative semantics in conceptualizing ontology from texts. The general basic question that this paper answer is whether semiotics can support ontology capture from texts.1429130
Assessing TD Macro-Management: A Nested Modelling Statistical Approach
No full textQuality improvement can be performed at the: (a) micro-management level: interventions applied at a fine-grained level (e.g., at a class or method level, by applying a refactoring); or (b) macro-management level: interventions applied at a large-scale (e.g., at project level, by using a new framework or imposing a quality gate). By considering that the outcome of any activity can be characterized as the product of impact and scale , in this paper we aim at exploring the impact of Technical Debt (TD) Macro-Management, whose scale is by definition larger than TD Micro-Management. By considering that TD artifacts reside at the micro-level, the problem calls for a nested model solution; i.e., modeling the structure of the problem: artifacts have some inherent characteristics (e.g., size and complexity), but obey the same project management rules (e.g., quality gates, CI/CD features, etc.). In this paper, we use the Under-Bagging based Generalized Linear Mixed Models approach, to unveil project management activities that are associated with the existence of HIGH_TD artifacts, through an empirical study on 100 open-source projects. The results of the study confirm that micro-management parameters are associated with the probability of a class to be classified as HIGH_TD, but the results can be further improved by controlling some project-level parameters. Based on the findings of our nested analysis, we can advise practitioners on macro-technical debt management approaches (such as " control the number of commits per day ", " adopt quality control practices ", and " separate testing and development teams ") that can significantly reduce the probability of all software artifacts to concentrate HIGH_TD. Although some of these findings are intuitive, this is the first work that delivers empirical quantitative evidence on the relation between TD values and project- or process-level metrics.11
Designing a Chatbot for Contemporary Education: A Systematic Literature Review
No full textA chatbot is a technological tool that can simulate a discussion between a human and a program application. This technology has been developing rapidly over recent years, and its usage is increasing rapidly in many sectors, especially in education. For this purpose, a systematic literature review was conducted using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) framework to analyze the developments and evolutions of this technology in the educational sector during the last 5 years. More precisely, an analysis of the development methods, practices and guidelines for the development of a conversational tutor are examined. The results of this study aim to summarize the gathered knowledge to provide useful information to educators that would like to develop a conversational assistant for their course and to developers that would like to develop chatbot systems in the educational domain.14950
Dying together: A convergence analysis of fatalities during COVID-19
No full textGovernments implemented countermeasures to mitigate the spread of the COVID-19 virus. This had a severe effect on the economy. We examine convergence patterns in the evolution of COVID-19 deaths across countries. We aim to investigate whether countries that implemented different measures managed to limit the number of COVID-19 deaths. We extend the most recent macro-growth convergence methodology to examine convergence of COVID-19 deaths. We combine a long memory stationarity framework with the maximal clique algorithm. This provides a rich and flexible club formation strategy that goes beyond the stationary/non stationary approach adopted in the previous literature. Our results suggest that strict measures (even belated) or an aggressive vaccination scheme can confine the spread of the disease while maintaining the strictness of the measures steady can lead to a burst of the virus. Finally, we observe that fiscal measures did not have an effect on the containment of the virus.28e0031
Opportunities and Challenges of Tangible XR Applications for 5G Networks and Beyond
No full textThe increasing popularity of virtual reality (VR) and augmented reality (AR) applications has unveiled the need for boosting the efforts of implementing extended reality (XR) to users. An analogous high interest from both academia and industry is being shown for tactile internet (TI). The ever-increasing use of virtualization technologies makes the usage of haptic communication even more important in order to create robust tangible systems, but also to achieve an optimal and faster balance among the interaction modalities, as well as between humans and machines. The current wireless mobile networks cannot provide ultra-low latency, massive computational capability, and high communication bandwidth, requirements which are crucial for applications such as extended reality and tactile internet. A simplified tangible XR system is proposed accompanied with the opportunities and challenges of such an implementation.12691
Team Formation: A Systematic Literature Review
No full textCollaborative activities require the formation of team(s), whose members may have weak or strong ties to each other, depending on the task to be completed. Team formation is a time consuming, complex, critical and essential process in the life cycle and development of the team, especially when the list of participants is disputed. To enhance learning and intellectual development in a team, it is important to select individuals based on specific prerequisites and create an environment that fosters genuine and effective interactions. However, the success of the team is not always guaranteed, and inappropriate team formation can lead to discouragement and hindered learning. As a result, researchers are exploring various clustering models and methods using best practices and other approaches to improve team formation and overcome these challenges. The process and the techniques used to form a team can vary depending on various factors, such as member characteristics, attributes, personalities, task, or context. However, despite the importance of team formation, there is no up-to-date comprehensive and systematic study to investigate and analyze its important techniques. Therefore, the main objective of this paper is to provide a comprehensive, detailed, systematic study, and to survey the most recent literature on team formation algorithms/techniques/mechanisms. This paper presents a systematic literature review (SLR) of recently published work investigating the team formation process, attributes, and techniques. Out of the 640 papers selected for review, 103 pass initial screening and accepted as papers related to team formation, and after a careful analysis, 30 papers meet the mandatory requirements/criteria defined in our protocol, using a specific selection and quality assessment method. The review reveals the current state of the art in the team formation literature and also sheds light on prospective topics for additional study. This systematic literature review can immediately assist academics and working professionals in understanding the evolving mechanisms and tactics of team formation by providing up to date information.182173
Conceptualizing and Validating a Model for Benchlearning Capability: Results from the Greek Public Sector
No full textThis paper aims to report on the development and assessment of a conceptual model for benchlearning capability, which facilitates sustainable performance improvement. Following an in-depth literature review, two main dimensions of benchlearning capability were identified. A focus group approach was used in order to establish the connection between these dimensions and the main construct (benchlearning capability). A questionnaire was designed and administered to 502 individuals from 74 organizations that used the Common Assessment Framework, and a total of 163 respondents replied. For the structural model assessment, the PLS-SEM technique was employed. Literature reveals that benchlearning encompasses both comparative evaluation and organizational learning mechanisms. Moreover, the focus group concluded that Organizational Learning Capability (OLC) and Benchmarking Capability (BMKC) are positively related to Benchlearning Capability (BLNC). The quantitative analysis showed that the factor OLC and BMKC are related positively and significantly to BLNC. This paper is the first attempt to approach the benchlearning capability construct and to validate its model. It is also a first attempt towards providing empirical evidence that could help public managers understand the BLNC concept and formulate accordingly the appropriate strategy for improving the benchlearning capability and therefore achieving sustainable performance in their organizations.152138