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Manolis Antonoyiannakis 《Journal of Informetrics》2018,12(4):1072-1088
Citation averages, and Impact Factors (IFs) in particular, are sensitive to sample size. Here, we apply the Central Limit Theorem to IFs to understand their scale-dependent behavior. For a journal of n randomly selected papers from a population of all papers, we expect from the Theorem that its IF fluctuates around the population average μ, and spans a range of values proportional to , where σ2 is the variance of the population's citation distribution. The dependence has profound implications for IF rankings: The larger a journal, the narrower the range around μ where its IF lies. IF rankings therefore allocate an unfair advantage to smaller journals in the high IF ranks, and to larger journals in the low IF ranks. As a result, we expect a scale-dependent stratification of journals in IF rankings, whereby small journals occupy the top, middle, and bottom ranks; mid-sized journals occupy the middle ranks; and very large journals have IFs that asymptotically approach μ. We obtain qualitative and quantitative confirmation of these predictions by analyzing (i) the complete set of 166,498 IF & journal-size data pairs in the 1997–2016 Journal Citation Reports of Clarivate Analytics, (ii) the top-cited portion of 276,000 physics papers published in 2014–2015, and (iii) the citation distributions of an arbitrarily sampled list of physics journals. We conclude that the Central Limit Theorem is a good predictor of the IF range of actual journals, while sustained deviations from its predictions are a mark of true, non-random, citation impact. IF rankings are thus misleading unless one compares like-sized journals or adjusts for these effects. We propose the Φ index, a rescaled IF that accounts for size effects, and which can be readily generalized to account also for different citation practices across research fields. Our methodology applies to other citation averages that are used to compare research fields, university departments or countries in various types of rankings. 相似文献
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A general model of performance and quality for one-stop e-Government service offerings 总被引:2,自引:2,他引:2
This paper introduces a framework and methodology for establishing indicators and metrics in order to assess the quality and performance of one-stop e-Government service offerings. The set of quality and performance indicators and metrics proposed has been derived in an outcomes assessment approach, based on the perspectives of e-Government service providers and end-users and following a goal-question-metric line of work that departs from some key quality and performance benefits. A methodology that employs the proposed framework to set improvement targets according to alternative scenarios is presented, and a strategy is elaborated for analyzing root causes of potential quality and performance shortcomings and undertaking appropriate countermeasures. Some results of application in a real case study, in the context of an EU-funded R&D project, are also provided. Finally, recommendations are given about usefulness of the proposed approach for e-Government service providers, as well as policy and decision-makers, and directions of future work are discussed in order to enhance the conceptual coverage of this approach, while at the same time not compromising its simplicity of application and generality of purpose. 相似文献
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Manolis Patiniotis 《Science & Education》2006,15(7-8):801-822
Greek society of the eighteenth century did not have the institutional or theoretical background for the development of an
original interest in scientific pursuits. The contact with the new scientific ideas aimed basically at the assimilation of
these ideas in the body of the existing contemplative philosophy and the context where such undertaking took place was exclusively
education. At the same time, education was the field where the political and ideological pursuits of various social groups
intersected. A quasi modernistic profile of the educational activity was especially favored by a new generation of scholars
who wished to assert their distinctive intellectual physiognomy, as well as by the emergent group of merchants who strove
to establish their distinctive cultural and political authority. As a result, the new interest in the sciences reflects the
confluence of the aims of these two social groups. The study of scientific textbooks, which were produced under these circumstances,
depicts the consequences of this confluence and brings to light some important aspects of the social and intellectual environment
within which the contact of Greek intellectual life with modern sciences occurred. 相似文献
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Patterns of Early‐Life Social and Environmental Exposures and Child Cognitive Development,Rhea Birth Cohort,Crete, Greece 下载免费PDF全文
Mariza Kampouri Andriani Kyriklaki Theano Roumeliotaki Katerina Koutra Despoina Anousaki Katerina Sarri Maria Vassilaki Manolis Kogevinas Leda Chatzi 《Child development》2018,89(4):1063-1073
Early‐life exposures are critical for later child cognitive development. McCarthy Scales of Children's Abilities (MSCA) were used to assess cognitive development of 700 preschoolers (Mage = 4.2 years), derived from the “Rhea” birth cohort, in Greece. Principal component analysis (PCA) was applied on prospectively collected exposure data. Six components were extracted; five of them were associated with child cognition. Higher parental social status, preschool attendance and less TV watching, nonsmoking during pregnancy and breastfeeding, and parental involvement in child life were protective factors of child cognition at 4 years. Increased child birth order was negatively associated with child cognition. Offspring's size at birth was not associated with any cognitive outcome. These findings reveal the importance of early‐life exposures to child cognitive development. 相似文献
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Mavrikis Manolis Rummel Nikol Wiedmann Michael Loibl Katharina Holmes Wayne 《Educational technology research and development : ETR & D》2022,70(3):691-712
Educational technology research and development - Educational technologies in mathematics typically focus on fostering either procedural knowledge by means of structured tasks or, less often,... 相似文献
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Manolis Wallace Kostas Karpouzis Mary Stefanou Ilias Maglogiannis Stefanos Kollias 《Education and Information Technologies》2004,9(3):271-289
The new educational approaches, as far as teaching of history in secondary education is concerned, are characterized by a shift away from sterile memorization and towards a critical approach of historical facts and phenomena; the aim is to contribute to both the development of students' historical concept and conscience and the promotion of critical thought. These teaching goals are pursued by promoting initiative of the students through self study assignments in the form of projects; students can be greatly supported in such tasks by computer-based applications, which can offer access to vast amounts of historical texts and data to be used next to the main scholar textbook and be analyzed by students. Still, existing applications seem to be quite inadequate for this purpose, as they require that the student be already informed on a matter, before the initiation of a quest for data. In this paper, we describe an intelligent information system that is designed to facilitate browsing of educational material and historical sources, thus allowing students to efficiently retrieve information on topics that are not yet known to them and expand in this way their historical knowledge. This can help in fulfilling the aforementioned teaching goals. Our system relies on the notion of the Electronic Road. 相似文献