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2215 research outputs found
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The effects of COVID-19 on firms’ liquidity: Evidence from the Athens Stock Exchange
No full textMotivated by the recent study of De Vito and Gómez (2020), this paper examines how the COVID-19 pandemic could influence the liquidity of Greek listed firms. It also explores the main factors that drive the level of operating cash flow (OCF). By simulating a decrease of 50% and 75% in sales, we perform stress-tests on three liquidity ratios for 154 listed firms on Athens Stock Exchange considering their degree of flexibility. For these firms, we also investigate if industry sector matters. Finally, OLS and quantile regression analysis is performed to gain a more detailed and complete picture of the determinants of the OCF. The findings show that on average a firm with limited flex-ibility, in the worst scenario, would consume its cash reserves in about two months. Furthermore, approximately 9% of all firms would become illiquid in about one year, whereas about 12% would become illiquid within two years. It is also observed that liquidity does not significantly variate across sectors. On average, as revealed by OLS method, the findings support that Total Governance, ROA and Female board significantly affect the OCF. The paper enables policymakers to perceive the magnitude of liquidity risk and improve their decision making.24115517
A generic sparse regression imputation method for time series and tabular data
No full textAlthough many missing data imputation methods have been proposed in the relevant literature, they focus on either time series or tabular data, but not on both. Hence, a generic sparse regression method for missing data imputation is proposed. The imputed values of a target feature are generated by solving a sparse least squares problem using a preconditioned iterative method based on generic approximate sparse pseudoinverse. Sparsity is introduced by dummy encoding existing or constructed (through discretization) categorical features. Extensive experiments were conducted on several datasets, and the results demonstrate the effectiveness of the method for both time series and tabular data.279411096
The effect of scaffolding programming games and attitudes towards programming on the development of Computational Thinking
No full textTeaching and learning Computational Thinking (CT) is at the forefront of educational interest. In the process of teaching and learning CT, learning strategies and tools play an important role. Efforts have been made to apply several learning strategies for teaching Computational Thinking. Among them, game-based learning and scaffolding are widely adopted. However, more research is needed on how the absence and presence of scaffolding strategies in programming games could affect students' cognitive CT learning gains. This study aims to investigate the effect of scaffolding programming games on the development of middle school students’ CT. In addition, herein we aim to explore the effect of students’ programming attitudes in their CT development. To this end, students were introduced to CT under two distinct experimental conditions: a scaffolding version of a programming game and a non-scaffolding version of the same game. Results report statistically significant differences between the pre- and post-intervention CT scores for all students and statistically significant improvement in learning outcomes in favor of the scaffolding group. In addition, the study hypothesized that attitudes towards programming would have an impact on students’ CT. Although this hypothesis has not been confirmed, the results suggest that students who have a less positive attitude towards programming could particularly benefit from scaffolding aspects in programming games.2866845686
SECDFAN: A Cyber Threat Intelligence System for Discussion Forums Utilization
No full textCyber Threat intelligence (CTI) systems offer new capabilities in the arsenal of information security experts, who can explore new sources of data that were partially exploited during the past decades. This paper deals with the exploitation of discussion forums as a source of raw data for a cyber threat intelligence process. Specifically, it analyzes the discussion forums’ characteristics and investigates their relationship with CTI. It proposes a semantic schema for the representation of data collected from discussion forums. Then, it applies a systematic methodology to design the reference architecture of the SECDFAN system, which handles the creation of CTI products following a comprehensive approach from the source selection to CTI product sharing and security experts’ collaboration. The final product of this work is the SECDFAN reference architecture. The contribution of this paper is the development of a CTI reference architecture of a system that, by design, handles all CTI-related issues for creating CTI products by analyzing the content of discussion forums.4161563
Leveraging Dialogue State Tracking for Zero-Shot Chat-Based Social Engineering Attack Recognition
No full textFeatured Application: Methods and techniques demonstrated in this work can be used to increase the effectiveness of chat-based social engineering attack detection systems. Human-to-human dialogues constitute an essential research area for linguists, serving as a conduit for knowledge transfer in the study of dialogue systems featuring human-to-machine interaction. Dialogue systems have garnered significant acclaim and rapid growth owing to their deployment in applications such as virtual assistants (e.g., Alexa, Siri, etc.) and chatbots. Novel modeling techniques are being developed to enhance natural language understanding, natural language generation, and dialogue-state tracking. In this study, we leverage the terminology and techniques of dialogue systems to model human-to-human dialogues within the context of chat-based social engineering (CSE) attacks. The ability to discern an interlocutor’s true intent is crucial for providing an effective real-time defense mechanism against CSE attacks. We introduce in-context dialogue acts that expose an interlocutor’s intent, as well as the requested information that she sought to convey, thereby facilitating real-time recognition of CSE attacks. Our work proposes CSE domain-specific dialogue acts, utilizing a carefully crafted ontology, and creates an annotated corpus using dialogue acts as classification labels. Furthermore, we propose SG-CSE BERT, a BERT-based model following the schema-guided paradigm, for zero-shot CSE attack dialogue-state tracking. Our evaluation results demonstrate satisfactory performance.138511
Harnessing small-scale events for sustainable tourism development and regional-level destination resilience
No full textSeasonality poses a significant challenge to the tourism sectors of many countries
around the world. While literature suggests that organizing events can help mitigate the
effects of seasonality in tourism destinations (Getz & Nilsson, 2004), limited research
has explored the in-depth perspectives of local professionals who face the personal and
financial difficulties caused by seasonality (Perić et al., 2022). Recently, small-scale
sport events have emerged as a key component of regional tourism offerings to reach
advantageous solutions towards sustainable tourism development (Chersulich Tomino
et al., 2020). Still, understanding the relevant priorities of local stakeholders is lacking.
This study aims to address this gap by examining the perspectives of local tourism
professionals representing regions from across Greece regarding the potential of smallscale events, specifically road races, in mitigating tourism seasonality and promoting
sustainable tourism development. Through qualitative interviews, a total of 164 local
professionals shared their experience as stakeholders of regional tourism destination
products (see Figure 1). Thematic analysis was employed to analyze the data collected
from these interviews. Professionals recognize seasonality as a challenge and suggest
initiatives incorporating small-scale events. The findings also demonstrate that regional
variations require localized strategies for stimulating tourism during low-season
periods, yielding positive economic and socio-cultural impacts. The study further
confirmed previous evidence (Zvaigzne et al., 2022) about the negative consequences
of seasonality on their regions and businesses, highlighting critical issues for
businesses, shedding light on the critical importance of implementing holistic
sustainable solutions to ensure survival and long-term viability. The study emphasizes
the significance of resilience in effectively addressing seasonality challenges and
promoting sustainable tourism practices. The findings serve as a valuable resource for
policymakers, destination managers, and tourism stakeholders seeking to promote
sustainable tourism practices
Digital Transformation in Healthcare: Technology Acceptance and Its Applications
No full textTechnological innovation has become an integral aspect of our daily life, such as wearable and information technology, virtual reality and the Internet of Things which have contributed to transforming healthcare business and operations. Patients will now have a broader range and more mindful healthcare choices and experience a new era of healthcare with a patient-centric culture. Digital transformation determines personal and institutional health care. This paper aims to analyse the changes taking place in the field of healthcare due to digital transformation. For this purpose, a systematic bibliographic review is performed, utilising Scopus, Science Direct and PubMed databases from 2008 to 2021. Our methodology is based on the approach by Wester and Watson, which classify the related articles based on a concept-centric method and an ad hoc classification system which identify the categories used to describe areas of literature. The search was made during August 2022 and identified 5847 papers, of which 321 fulfilled the inclusion criteria for further process. Finally, by removing and adding additional studies, we ended with 287 articles grouped into five themes: information technology in health, the educational impact of e-health, the acceptance of e-health, telemedicine and security issues.204340
Translation efficiency and directionally optimal scale
No full textThe aim of this paper is to show that instead of choosing the benchmark technology solely by means of maximal average productivities, a new whole range of options is opened up by using for this purpose the direction vector. By choosing any particular direction vector to evaluate technical efficiency we in fact predetermine by means of the relevant reflection vector the ray of average productivities we want to achieve. Then we may measure the extent of producing an inefficiently small (large) output by means of what we refer to as translation efficiency by comparing the average productivities of the projection of the observed input–output combination onto the best practice frontier and that of the graph translation homothetic technology. We can also determine the optimal production scale, which we refer to as directionally optimal scale, and which is defined conditionally on this vector of average productivities.140325927
Entrepreneurial new service development strategies: identifying critical success factors
No full textThe quickly shifting nature of the business environment generates ambiguity in the market place and poses a significant risk for decisions that will be made in the future. Managers do not know which factors are really key ingredients for the innovation process and how to allocate their resources to improve the success of service projects. This article aims to develop a predictive model which identifies the critical factors that impact the success of New Service Development (NSD) and promotes the entrepreneurial ecosystems in hospitality. In-depth, systematic interviews with hotel managers from all over Greece, based on questionnaires, were used to look into a total of 178 service projects. Factor and discriminant analysis were employed to evaluate the relative significance of the important factors of successful NSD and to determine whether new hotel services in Greece will succeed or fail. This research led to the creation of a prediction model that takes into account the unique qualities of services and can highlight the difference between new hotel services that are successful and those that aren't, which support managers to improve the NSD process, increase service performance and therefore enhance entrepreneurial ecosystems. The findings conclude that hotels offering more successful innovative services enhance specific ecosystem-related value. In the context of tourism, which mainly contributes to the Greek economy, service innovation might bring a competitive advantage to all the entities involved increasing the collaboration among actors, the level of employment and hotels' competitive advantage.53463865
Impact of the audit committee on audit fees: A review and future research agenda
No full textOver the last decades, research on the relationship between audit committees (ACs) and audit fees (AFs) has been increasing. Although numerous scholars have studied this topic, to the best of our knowledge, there is no systematic literature review (SLR) that provides a synthesized state of knowledge regarding this research area. To fill this gap this study presents a comprehensive systematic and objective review of existing research on the interaction between ACs and AFs. Using a sample of 78 articles, we find that most studies are empirical and country-specific and focus on developed markets in Europe and America. We also find that the majority of the examined papers use quantitative research methods by employing demand and supply theory either implicitly or explicitly. Further, we develop a categorization scheme, allocating the previous studies to six research themes (i.e. Composition, Diligence, Discrimination, Disclosure, Presence of (strong) AC and Compensation) and ten sub-themes. We then analyze each theme and its sub-themes providing details regarding its importance and impact on AFs and show that Diligence and Discrimination remain underexplored. Finally, we outline some potentially fruitful avenues for future research.102223897