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On the Impact of Different Inventory Policies on the Solution of the Inventory-Routing Problem with Strict Driving Hours’ Regulations and Driving Speed Limits
No full textThis work addresses a new Inventory-Routing Problem with realistic characteristics, such as strict driving hours’ regulations and driving speed limits. According to these realistic assumptions, the time needed to perform a route will be strictly bounded by an upper time limit based on the driving hours’ regulations provided by the European Commission. Moreover, the decisions about the speed level selection, for traveling between two network points, will be subject to specific driving speed limits. Moreover, the impact of two inventory policies, the classic (R,Q) replenishment policy and the flexible replenishment policy, on the total supply chain network cost is studied. The consideration of two inventory policies leads to the development of two mixed-integer linear programming models. The computational experiments were conducted on random, small-sized, problem cases, using the state-of-the-art solver, Gurobi. The impact of the two inventory policies on the supply chain network is investigated through a numerical analysis.5572Supply Chain Finance Modelling and Optimizatio
Defense Spending and Economic Growth: An Empirical Investigation in the Case of Greece
No full textThe existing empirical literature presents a limited number of country-specific studies that investigate the relationship between defense expenditures and economic growth. Despite the mounting concerns in Greece regarding the underwhelming economic growth of recent years and the persistent issue of excessive defense expenditures, no empirical study has yet investigated the effects of defense spending on economic growth in both the short and long run. The present study aims to address the aforementioned gaps in the literature by applying the autoregressive distributed lag (ARDL) bound testing approach to cointegration and analyzing the impact of defense spending, domestic investment, population growth, and literacy on economic growth in both the short and long term. The study employs the most up-to-date data available to ensure accuracy and relevance. The findings indicate that there is a positive impact of military expenditure on the economy’s growth in the short term. Nonetheless, when considering a longer time period, the same factor exerts an adverse influence on the growth of the economy. The findings of our investigation indicate that excessive military expenditures have significant adverse impacts on important drivers of economic growth, such as domestic investment, literacy rates, and population expansion, among others.299320Applied Economic Research and Trend
Measuring ESG risk premia with contingent claims
No full textWe propose a contingent claims approach for estimating ESG risk premia from market information and market participants' decisions. To this end, we infer the asset value dynamics via the structural model of Merton [1974, “On the Pricing of Corporate Debt: The Risk Structure of Interest Rates.” Journal of Finance 29: 449–470.] for a large panel of S&P 500 firms using an estimation algorithm that utilizes the information embedded in stock market prices, CDS spreads, and default probabilities. We find a statistically significant relationship between the ESG score and the volatility and drift terms of the asset value process, suggesting that ESG factors are structurally connected to the value of the firm. We establish a mapping between ESG scores and the cost of equity and debt as implied by firm's contingent claims, and derive estimates of the ESG risk premium across different ESG and leverage profiles. In addition, we break down the ESG risk premia by industry, and demonstrate how practitioners can adjust the weighed average cost of capital of ESG laggard firms for valuation and decision making purposes.31442745
What does matter in the success of a decentralized application? From idea to development
No full textContext: With the rise of blockchain, various applications are running in a decentralized manner, covering the needs of various end-users. Decentralized Applications (DApps) are becoming popular in numerous application domains, ranging from finance to games, and from Non-Fungible Tokens to security mechanisms. The success of a DApp, from a financial perspective, can be perceived as the market fragment that it captures, and the volume of transactions it generates. Objective: The goal of this study is to investigate the factors that are important for safeguarding (as much as possible) the financial success of a Decentralized Application. In this study, we focus on four management factors that could influence financial success: the context of the DApp (e.g., focusing on finance, games, entertainment), the intensity of development activities (e.g., number of: commits, forks, or branches of the repository), the size of the development team and the existence of project documentation. Method: We performed a case study on 122 DApps that were available through an open repository of smart contracts, namely State-of-the-DApps. By mining the repository, we recorded two metrics that capture the financial success of the application (number of users and volume of transactions) and explored their relation to the aforementioned factors. Results: The findings of the study suggest that the intensity of development activities is the most important factor for its financial success. Similarly, the context (i.e., the application domain) of the decentralized application is also a key-factor since it influences the number of users that the DApp will reach. Conclusions: Based on the findings, we suggest businesses that want to enter the market of decentralized applications to balance properly between technical and business parameters. For an application to be successful, it requires both an intensive development process, but also a careful consideration of the application domain.16910741
Vulnerability prediction using pre-Trained models: An empirical evaluation
No full textThe rise of Large Language Models (LLMs) has provided new directions for addressing downstream text classification tasks, such as vulnerability prediction, where segments of the source code are classified as vulnerable or not. Several recent studies have employed transfer learning in order to enhance vulnerability prediction taking advantage of the prior knowledge of the pre-Trained LLMs. In the current study, different Transformer-based pre-Trained LLMs are examined and evaluated with respect to their capacity to predict vulnerable software components. In particular, we fine-Tune BERT, GPT-2, and T5 models, as well as their code-oriented variants namely CodeBERT, CodeGPT, and CodeT5 respectively. Subsequently, we assess their performance and we conduct an empirical comparison between them to identify the models that are the most accurate ones in vulnerability prediction.162024 32nd International Conference on Modeling, Analysis and Simulation of Computer and Telecommunication Systems (MASCOTS
Machine learning in accounting and finance research: a literature review
No full textIn recent years, scholars in accounting and finance have shown a growing interest in employing machine learning for academic research. This study combines bibliographic coupling and literature review to analyze 575 papers from 93 well-established journals in the field of accounting and finance published between 1996 and 2022, and addresses three interrelated research questions (RQs): RQ1 How is research on the impact of machine learning on accounting and finance developed? RQ2 What is the focus within this corpus of literature? RQ3 What are the future avenues of machine learning in accounting and finance research? We adopt a critical approach to the research foci identified in the literature corpus. Our findings reveal an increased interest in this field since 2015, with the majority of studies focused either on the US market or on a global scale, with a significant increase in publications related to Asian markets during 2020–2022 compared to other regions. We also identify that supervised models are the most frequently applied, in contrast to unsupervised models, which mainly focus on clustering applications or topic extraction through the LDA algorithm, and reinforcement models, which are rarely applied, yield mixed results. Additionally, our bibliographic analysis reveals six clusters, and we discuss key topics, current challenges and opportunities. Finally, we outline machine learning constraints, highlighting common pitfalls, and proposing effective strategies to overcome current barriers and further advance research on this issue.6341431147
A Holistic Approach to Define Important Digital Skills for the Digital Society
No full textNowadays, transactions carried out with digital currencies are increasing. Modern societies are asked to respond to growing challenges related to the management of digital currencies in their daily lives. However, due to the lack of digital skills of users, the management of digital currencies hides risks. To the best of our knowledge, the originality of the current research lies in the act of combining the concept of digital skills with the use of digital currencies. After all, the use of digital currencies is constantly increasing, which means that citizens should familiarize themselves with their use, an element that makes this study valuable for digital societies. Digital skills effectively contribute to the development of digital societies because they increase the employment of citizens, facilitate access to information, and contribute to the social inclusion of individuals through digital communication, while also increasing efficiency and productivity in the workplace. Also, the government and banking institutions can more effectively sensitize citizens to digital skills for more effective use of digital currencies. In this way, tax payments will be facilitated, the use of e-wallets will be safer, and e-governance will be greatly promoted, while the quality of banking services will be improved. The methodology of this study was based on the Digital Competence Framework for Modern Societies (DigComp) and was applied through a questionnaire completed by 443 respondents. The main objective was to evaluate their digital skills from the perspective of digital currency use. The analysis of the responses was carried out by using Structural Equation Modeling (SEM). The most important result from this research reveals that users of digital currencies are significantly capable of developing communication to solve everyday problems. At the same time, users of digital currencies mostly detect digital threats and effectively manage fake news without being affected by them. However, users of digital currencies consider that security issues are important, but only for transactions and not for their supporting functions. The study concludes with suggestions for improving the experience of digital currency users through individual actions, thus having a positive impact on the state and banking institutions.14712
The Effect of Physical and Virtual Inquiry-Based Experiments on Students’ Attitudes and Learning
No full textInvolving students in laboratory and inquiry-based activities can help them understand the concepts of physics. However the learning process should not only focus on the concepts. Moreover, the advantages of using virtual or physical labs are still under examination. The purpose of this study is to analyse which of the two modes (virtual or physical) is the most effective for high-school students, in terms of conceptual understanding and attitudes. The criteria for this comparison are (a) the contribution of these two modes to the improvement of conceptual understanding and (b) the students’ attitudes towards both modes of laboratory. The participants were high-school students of 3rd grade in two different groups. For the purpose of the study, four educational scenarios were created: two in the field of Mechanics and two in that of Electricity. The study revealed no statistically significant difference regarding students’ experimenting in either lab mode. Moreover, students’ attitudes towards both virtual and physical labs were similarly positive. We assume that these results may contribute to a broader perspective on choosing the lab mode when designing activities, given the fact that both the understanding and attitudes of the students are similar in the cases examined. Thus, the final choice of modality should be based on other factors, such as the adequacy of equipment, the educational conditions (e.g. distance education) and the specific learning goals set by the teacher.33334936
Uncertainty and financial asset return spillovers: are they related? Empirical evidence from three continents
No full textThis paper focuses on financial asset return spillovers and economic policy uncertainty spillovers in three continents (Europe, America, and Asia) in the last few decades. We examine three financial asset markets (stock, bond, and foreign exchange). Spillovers are measured using the Diebold–Yilmaz spillover index. In the first part, we measure the size of spillovers and find a significant increase in spillovers during the global financial crisis, the European sovereign crisis, and the recent pandemic. In the second part, we test for the effect of uncertainty spillovers on financial asset return spillovers. Using rolling impulse response functions, we obtain the following results: First, the responses of financial markets spillovers to uncertainty spillovers are time-varying and are mostly positive. Second, the highest responses in financial market return spillovers to uncertainty spillovers occur in America and the smallest responses in financial market return spillovers occur in Europe. Third, among the three financial markets, the highest responses apply to the foreign exchange market. Finally, the largest responses during the pandemic apply in Europe.6751891191
Exploring the Relationships between the Enablers and Results Criteria of the EFQM Model 2013 in the Context of the Greek Public Administrative Services
No full textThis study presents a first attempt to apply and validate the European Foundation for Quality Management (EFQM) Model 2013 as a framework in the context of public administrative services in Greece, and to explore the relationships between the model’s enablers and results criteria. The methodological approach adopted was quantitative research with a structured questionnaire, while partial least squares structural equation modeling (PLS-SEM) was applied to validate the model and test the cause–effect relationships between the enablers and results on a national sample of 155 managers. The results confirmed the reliability and validity of the EFQM Model 2013 in the context of this study and revealed significant relationships between the model’s enablers and results. In addition, the empirical findings of this study may improve our understanding of the underlying relationships between the EFQM model criteria, but should not be generalized, as this study only concerned Greek public administrative services. Finally, this study may provide valuable insights to managers and governing bodies responsible for policy-making about the significance and magnitude of the relationships between the enablers and results criteria so that they can develop strategies to improve the operational and strategic performance of the Greek public administrative services.1447