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91.
《Journal of Informetrics》2020,14(4):101072
This work analyzes the variation over time of the effect of geographic distance on knowledge flows. The flows are measured through the citations exchanged between scientific publications, including and excluding self-citations. To calculate geographic distances between citing and cited publication, each publication is associated with a “prevailing” territory, according to the authors’ affiliations. We then apply a gravity model to account for the research size of the territories, in terms of cognitive proximity of citing-cited publications. The field of observation is the 2010–2017 world publications citing the 2010–2012 Italian publications, as indexed in the Web of Science. The results show that in domestic knowledge flows, geographic proximity remains an influential factor through time, although with differences among disciplines and trends of attenuating effects. Finally, we replicate the analyses of knowledge flows but with the exclusion of self-citations: in this manner the effect of geographic proximity seems reduced, particularly at the national scale, but the differences (with vs without self-citations) lessen through time. As shown in previous works, the effect of distance on continental flows is modest (imperceptible for intercontinental flows), yet here too time has some influence, including concerning exclusion of self-citations. 相似文献
92.
《Journal of Informetrics》2020,14(1):101010
This paper analyses the influence of geographic distance on knowledge flows, measured through citations to scientific publications. Previous works using the same approach are limited to single disciplines. In this study, we analyse the Italian scientific production in all disciplines matured in the period 2010–2012. To calculate the geographic distances between citing and cited publications, each one is associated with a “prevalent” territory on the basis of the authors’ affiliations. The results of the application of a gravity model, estimated using ordinary least squares regression, show that despite the spread of IT, geographic distance continues to be an influential factor in the process of knowledge flows between territories. In particular, the analysis reveals that the effect of geographic distance on knowledge flows is significant at the national level, not negligible at the continental level, but completely irrelevant at the intercontinental level. 相似文献
93.
《Journal of Informetrics》2020,14(4):101077
Because humans have limited resources and capacities to digest and comprehend the unprecedented amount of information bombarding today’s world, human attention is a scarce resource and the problem of information overload is becoming increasingly serious. In this study we aim to contribute to an understanding of how humans make decisions about the value of complex sources of information, specifically in the context of online scholarly platforms, online news, and social media. We thus use almost 5000 research-based VoxEU texts, together with the corresponding authors’ characteristics, to test whether, as an evolutionary approach would suggest, author success, skills, and prestige serve as strong cues in readers’ attentional decisions, by analyzing reading, sharing, and searching behaviors. In addition to finding strong support for this assumption, we also show that readers respond to such visual cues as article title, number of words in the abstract, and/or text content, with a clear favoring of figures over tables. 相似文献
94.
《Journal of Informetrics》2020,14(1):101004
The number of received citations have been used as an indicator of the impact of academic publications. Developing tools to find papers that have the potential to become highly-cited has recently attracted increasing scientific attention. Topics of concern by scholars may change over time in accordance with research trends, resulting in changes in received citations. Author-defined keywords, title and abstract provide valuable information about a research article. This study performs a latent Dirichlet allocation technique to extract topics and keywords from articles; five keyword popularity (KP) features are defined as indicators of emerging trends of articles. Binary classification models are utilized to predict papers that were highly-cited or less highly-cited by a number of supervised learning techniques. We empirically compare KP features of articles with other commonly used journal-related and author-related features proposed in previous studies. The results show that, with KP features, the prediction models are more effective than those with journal and/or author features, especially in the management information system discipline. 相似文献
95.
《Journal of Informetrics》2020,14(1):101006
We present two ways (instantaneous and cumulative) to transform bibliographic networks, using the works’ publication year, into corresponding temporal networks based on temporal quantities. We also show how to use the addition of temporal quantities to define interesting temporal properties of nodes, links and their groups thus providing an insight into evolution of bibliographic networks. Using the multiplication of temporal networks we obtain different derived temporal networks providing us with new views on studied networks. The proposed approach is illustrated with examples from the collection of bibliographic networks on peer review. 相似文献
96.
《Journal of Informetrics》2020,14(1):100988
This paper proposes a simple, flexible, axiom-based mechanism for facilitating the comparison between a scholar's citation count and the visibility of the journals wherein the scholar's articles were published. The goal is to help research review bodies easily grasp the distinction these two forms of scholarly accomplishment and to provide a transparent way to articulate expectations about them to scholars. The approach is demonstrated using a widely applied and cooperative functional form that can reflect, via different parameter values, a wide range of possible beliefs about the relative merits of citation counts and journal visibility. 相似文献
97.
Linda C. Smith 《Information processing & management》1976,12(3):189-222
A survey is given of the potential role of artificial intelligence in retrieval systems. Papers by Bush and Turing are used to introduce early ideas in the two fields and definitions for artificial intelligence and information retrieval for the purposes of this paper are given. A simple model of an information retrieval system provides a framework for subsequent discussion of artificial intelligence concepts and their applicability in information retrieval. Concepts surveyed include pattern recognition, representation, problem solving and planning, heuristics, and learning. The paper concludes with an outline of areas for further research on artificial intelligence in information retrieval systems. 相似文献
98.
[目的/意义]当前学术界对网络舆情的概念内涵描述缺少规范、统一、明确的界定,对该领域的相关概念及其关系进行辨析有利于助推后续研究的发展。[方法/过程]在深入调查和比较现有文献的基础上,从网络舆情领域涉及的研究对象和概念分布入手,重点对网络舆情的研究对象、术语表达及其相互关系进行比较和辨析,并在综合当前研究环境下对网络舆情内涵表述进行广义性界定,同时对图书情报领域网络舆情研究的发展启示进行了分析。[结果/结论]有助于明晰网络舆情在不同学科或领域中边界与范畴。 相似文献
99.
Metrics derived from user visits or sessions provide a means of evaluating Websites and an important insight into online information seeking behaviour, the most important of them being the duration of sessions and the number of pages viewed in a session, a possible busyness indicator. However, the identification of session (termed often ‘sessionization’) is fraught with difficulty in that there is no way of determining from a transactional log file that a user has ended their session. No one logs out. Instead a session delimiter has to be applied and this is typically done on the basis of a standard period of inactivity. To date researchers have discussed the issue of a time out delimiter in terms of a single value and if a page view time exceeds the cut-off value the session is deemed to have ended. This approach assumes that page view time is a single distribution and that the cut-off value is one point on that distribution. The authors however argue that page time distribution is composed of a number of quite separate view time distributions because of the marked differences in view times between pages (abstract, contents page, full text). This implies that a number of timeout delimiters should be applied. Employing data from a study of the OhioLINK digital journal library, the authors demonstrate how the setting of a time out delimiter impacts on the estimate of page view time and the number of estimated session. Furthermore, they also show how a number of timeout delimiters might apply and they argue that this gives a better and more robust estimate of the number of sessions, session time and page view time compared to an application of a single timeout delimiter. 相似文献
100.
AbstractThis article develops a conceptual model of users’ and designers’ knowledge roles in the information and communication technology design process. The “ideal” center at the intersection of the axes for division of knowledge work and privileging of knowledges represents a balanced distribution of knowledge work between users and designers and an avoidance of privileging either group over the other. The article then applies this model to analyses of the design process for six video games wherein the knowledges of Indigenous peoples in North America were mobilized. It concludes by discussing implications for research and design practice, particularly for broadening the participation and self-articulation of marginalized groups. 相似文献