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Multivariate Cointegration and Temporal Aggregation: Some Further Simulation Results
No full textWe perform Monte Carlo simulations to study the effect of increasing the frequency of observations and data span on the Johansen (J Econ Dyn Control 12(2–3):231–254, 1988; Likelihood-based inference in cointegrated vector autoregressive models, Oxford University Press, Oxford, 1995) maximum likelihood cointegration testing approach, as well as on the bootstrap and wild bootstrap implementations of the method developed by Cavaliere et al. (Econometrica 80(4):1721–1740, 2012; Econ Rev 33(5–6):606– 650, 2014). Considering systems with three and four variables, we find that when both the data span and the frequency vary, the power of the tests depend more on the sample length. We illustrate our findings by investigating th existence of long-run equilibrium relationships among four indicators prices of coffee.591597
On the English (1931) and Spanish (1932) translations of von Economo's classic monograph on encephalitis lethargica
No full textThe "second" seminal monograph by Constantin von Economo on encephalitis lethargica appeared in print in German in 1929, following his initial report of the disease (eponymously associated with his name) before the Viennese Society of Psychiatry and Neurology and the publication of his "first" monograph on the subject in 1917. The 1929 book was translated into English and Spanish and published by Humphrey Milford in Oxford and Espasa-Calpe in Madrid in 1931 and 1932, respectively. The present article gives some details of those translations and the neuropsychiatrists who produced them. Moreover, four previously unpublished letters by von Economo are presented, relating to the English edition of Die Encephalitis lethargica. These letters are of historical interest, as they provide insights into von Economo's personality and view of the translation.31130-444
Organizational determinants as antecedent factors of export marketing strategy archetypes of agri-food firms: a three country analysis
No full textPurposeThis paper researches export marketing strategy (EMS) archetypes of agri-food exporters and organizational determinants that pose as their antecedent factors, using resource-based, dynamic capabilities and contingency theories as theoretical framework in a multi-county research setting. A twofold objective is specified – to explore hitherto used EMS and to examine differences between agri-food exporters based on organizational determinants.Design/methodology/approachComparative research design, quantitative methodology, an etic/emic approach, descriptive and causal data analyses were employed. EMS archetypes were portrayed on radial plots, while six hypotheses were tested using MANOVA.FindingsThe tactical coordinator was identified as a universal EMS archetype. Diversity of archetypes was found as results of the effect of organizational determinants, confirming their ambivalent impacts rooted in the resources, capabilities and contingencies exporters have to face.Research limitations/implicationsMain limitations arise from the sample choice in international business, concentration only on organizational determinants, survey as a data collection technique and reliance on self-report data from managers. Nevertheless, several theoretical and practical implications are defined.Originality/valueTo the authors’ knowledge, this paper is the first to apply the EMS archetype perspective to the agri-food industry in a developing country context and in an economic crisis context. Its multi-theory approach is supplemented with researched countries' national culture perspective and institutional background to extend understanding of agri-food firms' EMS archetypes.12441400141
POPULATION AGING AND INVENTIVE ACTIVITY
No full textThis research empirically establishes and interprets the hypothesis that the relationship between population aging and inventive activity is hump-shaped. We estimate a reduced form, hump-shaped relationship in a panel of 33 OECD countries over the period 1960–2012, as well as in a panel of 248 NUTS 2 regions in Europe over the period 2001–2012. The increasing part of the hump may be associated with various channels including the acknowledgement that population aging requires inventive activity to guarantee current and future standards of living, or the observation that older educated workers are more innovative than their young peers. The decreasing part may reflect the tendency of aging societies to lose dynamism and the willingness to take risks.2651127116
Recent Trends in Sustainable Supply-Chain Optimization
No full textSupply-chain sustainability refers to the optimal balance between economic, environmental, and societal criteria during decision-making processes. This chapter presents a comprehensive review of recent research contributions on sustainable supply-chain optimization. The selected articles have been classified according to several criteria. More specifically, an initial classification has been performed based on the sustainability concerns taken under consideration in each study. Next, a classification has been provided based on decision levels, and finally, the reviewed works have been categorized according to the available solution methods. The chapter is closing with some main insights and suggestions for future research.123Handbook of Smart Energy System
Scheduling of Heterogeneous Services by Resolving Conflicts
No full textFifth generation (5G) new radio introduced flexible numerology to accommodate heterogeneous services. However, optimizing the scheduling of heterogeneous services with differing delay and throughput requirements over 5G new radio is a challenging task. In this paper, we investigate near optimal, low complexity scheduling of radio resources for ultra-reliable low-latency communications (URLLC) when coexisting with enhanced mobile broadband (eMBB) services. We demonstrate that maximizing the sum throughput of eMBB services while servicing URLLC users over a fixed length time-frequency grid, is, in the long-term, equivalent to minimizing the number of URLLC placements in the time-frequency grid; this is the consequence of reducing the number of infeasible placements for eMBB, to which we refer to as "conflicts." To meet this new objective, we evaluate the performance of new, conflict-aware heuristics, consisting of a family of "greedy" and a lightweight heuristic inspired by bin packing optimization, all of near optimal performance. Moreover, having shed light on the impact of conflict in layer-2 scheduling, we investigate non-orthogonal multiple access (NOMA) as a potential approach for conflict resolution leveraging superposition coding. The superior performance of NOMA with respect to OMA, thanks to resolving conflicts, is showcased by extensive numerical results.10365763659
SDK4ED: A platform for technical debt management
No full textTechnical debt management is of paramount importance for the software industry, since maintenance is the costlier activity in the software development lifecycle. In this article, we present the SDK4ED platform that enables efficient technical debt management (i.e., measurement, evolution analysis, prevention, etc.) at the code level, and evaluate its capabilities in an industrial setting. The SDK4ED platform is the outcome of a 3-year project, including several software industries. Since, the research rigor of the approaches that reside in SDK4ED have already been validated, in this work we focus: (a) on the presentation of the platform per se; (b) the evaluation of its industrial relevance; (c) the usability of the platform; as well as (d) the financial implications of its usage.5281879190
Strategy implications of IS planning: Executives’ perceptions on firm performance
No full textThis paper aims to explore the effect on business performance of both Information Technology (IT) and business strategy. All data were obtained form 294 IS executives in Greek Small-Medium Enterprises (SMEs) and analyzed using Ordinal Regression Analysis. As the results of this survey indicate, SMEs cannot increase business value without strategic planning. IT executives should be aware of IT issues because this can be an obstacle for the organization and will prevent them achieving their planning goals and increasing the value of the business.59310362
Teachers’ Views on Integrating Augmented Reality in Education: Needs, Opportunities, Challenges and Recommendations
No full textThe integration of augmented reality (AR) in education is promising since it enhances teaching and offers more engaging and appealing learning experiences. Teachers can have a catalytic role towards the adoption of AR in education; therefore, their perspectives with regard to AR in teaching and learning are very important. The current study explores teachers’ views on the integration of AR in education through an open-ended questionnaire that has been answered by 93 educators worldwide. A set of digital skills that can support student-centered pedagogies in an appropriate infrastructure are the main requirement for effective teaching with AR. Among the perceived benefits and opportunities are interactive teaching and learning, increased interest and engagement, better understanding of complex concepts. As barriers, participants reported the lack of AR educational applications, the cost of buying and maintaining AR equipment and resources, the lack of teachers’ and students’ digital skills, classroom management issues, and security and ethical issues. Moreover, survey participants highlighted the need for raising teachers’ awareness for the added value of AR in education and the need for teachers’ continuous professional development. Implications and future research recommendations on the integration of AR in education are discussed.1512
The Character of the Greek Revolution of 1821
No full textThe article explains the social conditions and changes that were taking place inthe Balkans during the Ottoman Empire. These changes were slow in the 15th and 16thcenturies, became somewhat faster during the 17th, and accelerated in the last quarterof the 18th century. That is the period of the Industrial Revolution and the domination ofcapitalism in Western Europe. The article details this transformation and the maturationof the rupture conditions within the Ottoman Empire that gave rise to the GreekRevolution of 1821. Particular attention is paid to the emerging social classes and theirdistinct roles in the revolution. The article concludes by arguing that although the GreekRevolution of 1821 possesses its idiosyncratic features, nevertheless it bears notablesimilarities to the French Revolution.60271