共查询到20条相似文献，搜索用时 555 毫秒
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《Journal of Informetrics》2007,1(2):115-122
Evolution of information production processes (IPPs) can be described by a general transformation function for the sources and for the items. It generalises the Fellman–Jakobsson transformation which only works on the items.In this paper the dual informetric theory of this double transformation, defined by the rank-frequency function, is described by, e.g. determining the new size-frequency function. The special case of power law transformations is studied thereby showing that a Lotkaian system is transformed into another Lotkaian system, described by a new Lotka exponent. We prove that the new exponent is smaller (larger) than the original one if and only if the change in the sources is smaller (larger) than that of the items.Applications to the study of the evolution of networks are given, including cases of deletion of nodes and/or links but also applications to other fields are given. 相似文献
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The original Lotka's Law refers to single scientist distribution, i.e. the frequency of authors Ai with i publications per author is a function of i: Ai = f(i). However, with increasing collaboration in science and in technology the study of the frequency of pairs or triples of co-authors is highly relevant. Starting with pair distribution well-ordered collaboration structures of co-author pairs will be presented, i.e. the frequency of co-author pairs Nij between authors with i publications per author and authors with j publications per author is a function of i and j: Nij = f(i, j) using the normal count procedure for counting i or j. We have assumed that the distribution of co-author pairs’ frequencies can be considered to be reflection of a social Gestalt and therefore can be described by the corresponding mathematical function based on well-known general characteristics of structures in interpersonal relations in social networks. We have shown that this model of social Gestalts can better explain the distribution of co-author pairs than by a simple bivariate function in analogy to Lotka's Law. This model is based on both the Gestalt theory and the old Chinese Yin/Yang theory. 相似文献
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《Journal of Informetrics》2014,8(3):449-477
This paper analyzes several well-known bibliometric indices using an axiomatic approach. We concentrate on indices aiming at capturing the global impact of a scientific output and do not investigate indices aiming at capturing an average impact. Hence, the indices that we study are designed to evaluate authors or groups of authors but not journals. The bibliometric indices that are studied include classic ones such as the number of highly cited papers as well as more recent ones such as the h-index and the g-index. We give conditions that characterize these indices, up to the multiplication by a positive constant. We also study the bibliometric rankings that are induced by these indices. Hence, we provide a general framework for the comparison of bibliometric rankings and indices. 相似文献
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期刊h型指数与论文数量和被引的关系实证 总被引：3，自引：0，他引：3
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L. Egghe 《Journal of Informetrics》2011,5(3):439-445
We define the generalized Wu- and Kosmulski-indices, allowing for general parameters of multiplication or exponentiation. We then present formulae for these generalized indices in a Lotkaian framework.Next we characterise these indices in terms of their dependence on the quotient of the average number of items per source in the m-core divided by the overall average (m is any generalized Wu- or Kosmulski-index).As a consequence of these results we show that the fraction of used items (used in the definition of m) in the m-core is independent of the parameter and equals one divided by the overall average. 相似文献
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科学家博客h指数评价及其相关性分析 总被引：1，自引：0，他引：1
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Journal weighted impact factor: A proposal 总被引：3，自引：0，他引：3
The impact factor of a journal reflects the frequency with which the journal's articles are cited. It is the best available measure of journal quality. For calculation of impact factor, we just count the number of citations, no matter how prestigious the citing journal is. We think that impact factor as a measure of journal quality, may be improved if in its calculation, we not only take into account the number of citations, but also incorporate a factor reflecting the prestige of the citing journals relative to the cited journal. In calculation of this proposed “weighted impact factor,” each citation has a coefficient (weight) the value of which is 1 if the citing journal is as prestigious as the cited journal; is >1 if the citing journal is more prestigious than the cited journal; and is <1 if the citing journal has a lower standing than the cited journal. In this way, journals receiving many citations from prestigious journals are considered prestigious themselves and those cited by low-status journals seek little credit. By considering both the number of citations and the prestige of the citing journals, we expect the weighted impact factor be a better scientometrics measure of journal quality. 相似文献
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《Journal of Informetrics》2023,17(1):101366
Inspired by the Lorenz curve for evenness or concentration, and the corresponding axioms, we construct a theory leading to the notion of global impact. In this theory, we construct a relation that plays the role of the Lorenz dominance order for evenness or concentration theory. The notion of global impact that we obtain is such that well-known global impact bundles such as percentiles, the cumulative number of items produced by the x most productive sources, the average production of the x most productive sources, the generalized h- and g-indices, and the highest number of citations indeed measure impact in our sense of the word. 相似文献
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Our content analysis of 2,075 campaign stories aired by 3 broadcast and 3 cable networks during the 2004 presidential campaign revealed that female and non-White reporters at broadcast networks were generally more aggressive in their source use when compared to their male and White colleagues, using a greater number of sources and in most cases also allotting the sources more time. Female and non-White reporters at cable networks also tended, although less consistently and to a lesser extent, to use and give more time to female and non-White sources. 相似文献
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Variables subject to an order restriction, for instance Y ≤ X, have a bivariate distribution over a non-rectangular joint domain that entails a non-null and potentially large structural relation even if the variables show no association (in the sense that particular ranges of values of X do not co-occur with particular ranges of values of Y). Order restrictions affect a number of scientometric indices (including the h index and its variants) that are routinely subjected to correlational analyses to assess whether they provide redundant information, but these correlations are contaminated by the structural relation. This paper proposes an alternative definition of association between variables subject to an order restriction that eliminates their structural relation and reverts to the conventional definition when applied to variables that are not subject to order restrictions. This alternative definition is illustrated in a number of theoretical cases and it is also applied to empirical data involving scientometric indices subject to an order restriction. A test statistic is also derived which allows testing for the significance of an association between variables subject to an order restriction. 相似文献
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[目的/意义] 追求优质内容生产还是知识付费情境建设，是知识付费平台需要面对的重要权衡，本研究旨在为知识付费平台建设和知识营销策略优化提供指导。[方法/过程] 采用定性比较分析方法，探究影响在线用户知识付费行为的主要因素及前因构型，分析"内容"（Content）"情境"（Context）"辨识"（Conciousness）各自作用和协同并发对用户知识付费行为的复杂影响机理。[结果/结论] 根据实证析出的典型路径发现：①"内容-情境-辨识"（CCC）联动匹配的组态能够激活研究框架，驱动在线用户"行为"（Behavior）选择生成；②付费产品中"内容质量*内容效用*合法化"是用户需求响应的核心条件，付费情境中"群体规范"是用户知识扩散行为的充分条件；③存在5种高解释力的复杂解结果，对网络交易论以及本文倡导的用户知识付费观的影响及整体效益有所差异；④与许多文献结论不同的是：受限认知能够成为用户行为决策的支持性因素，而涉入认知却成为组态中起调和性作用的变量，需要与具体情境因素共同促成用户选择；⑤不同参与条件的搭配存在"结果等同但效益不等同"的等价替代作用，具体条件及其组合可以通过等价替代的方式促成用户知识付费行为。 相似文献
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E-governance, with reference to the relationship between the individual and the state, develops in dense networks of human and technological actors. However, mobilization of information technology in e-governance is not a straightforward instantiation of such ambitions but rather a tinkering process in which actors and their interests are combined and transformed. In this paper we examine this idea by investigating the development of a Swedish national public healthcare portal representing a complex, multilevel, and political environment. In this endeavour, the principle of symmetry from Actor-Network Theory and an event-based approach in the analysis play important roles. We show that the development process involves envisioning the future (even if vaguely), implementing concrete ideas about technological functionality and platforms, reconciling diverse interests, prioritizing and framing political concerns and breakdowns, and working toward realization of abstract goals. In this process, the technological actors play a role as important as that of the human actors. The paper concludes that e-governance relationships emerge that rest upon socio-material pragmatics influenced by political transformations that are often unanticipated. 相似文献
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Nicole S. Cohen 《The Communication Review》2015,18(2):98-122
This paper examines some of the labor processes involved inthe expansion of digital journalism to comment on the nature and implications of transformations in journalistic work in a digital age. Specifically, I survey four practices that stand out as putting pressure on traditional journalism production: outsourcing, unpaid labor, metrics and measurement, and automation. Although these practices are unevenly incorporated into mainstream news production (and in some cases are still marginal), they demonstrate viable options for media corporations seeking to streamline production. Drawing on labor process theory, I emphasize that media corporations use strategies of efficiency and rationalization to lower labor costs. Unpaid labor, robot reporters, algorithms, and outsourcing demonstrate that changes in the media production process are not the inevitable results of technology but, as the long history of journalism and technological change demonstrates, strategies for lowering labor costs. 相似文献
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感知价值视角下数字健康APP用户持续采纳意愿的影响因素及路径研究:基于fsQCA方法 总被引：1，自引：0，他引：1
[目的/意义]数字健康APP用户存留率较低问题一直难以解决,本研究旨在明确影响用户持续采纳数字健康APP的感知价值因素及其影响路径,为未来数字健康APP的改进提供参考。[方法/过程]基于感知价值视角,利用内容分析和模糊集定性比较分析的研究方法,从用户对数字健康APP的负面评论中进行持续采纳因素的归纳,并依据归纳出的影响因素探究导致用户持续采纳数字健康APP的组态。[结果/结论]研究发现,系统价值、更新价值、环境价值、问诊价值、交易价值和安全价值是影响用户持续采纳数字健康APP的影响因素;通过fsQCA3.0共生成导致用户持续采纳的3条有效组态,分别为CA1：高更新价值*高交易价值*高安全价值*高问诊价值;CA2：高更新价值*高交易价值*高安全价值*高环境价值*高系统价值;CB：低系统价值*高更新价值*高安全价值*高问诊价值*高环境价值。最后,笔者对影响因素及组态进行分析,为数字健康APP的未来发展提供实践启示。 相似文献
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O. V. Kirillova 《Scientific and Technical Information Processing》2007,34(4):231-239
Using data from Ulrich’s Periodicals Directory, and the extent of coverage by abstract information resources and indices, the worldwide output of periodicals and proceedings (including those represented in electronic form) is studied. A quantitative characterization of the entire output of worldwide editions, as well as its abstracted portion is given. To provide complete reception of needed subject information and cover a maximum number of periodicals using an information system, a method for selecting several databases, which makes it possible to get a maximum coverage of primary sources with a certain amount of duplication, is proposed. Data on abstracting are obtained as the result of analyzing the input stream of approximately 700 databases and indices. Basic statistics for the abstracted stream are given for a number of companies: VINITI (All-Russia Institute for Scientific and Technical Information, Russian Academy of Sciences), CSA (Chemical Abstracts Service), Thomson Corporation, Elsevier, CABI Publishing, CAS (Cambridge Scientific Abstracts), and several others. A list of 25 of the largest abstract journals and referral databases, with respect to the number of periodicals represented in them, is given. 相似文献
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《Journal of Informetrics》2022,16(4):101340
We show that the h-index, g-index, ψ-index, and p-index, are related through the inequalities: h ≤ p ≤ g ≤ ψ. Moreover, this relation is proved theoretically in the mathematical framework of Lotkaian informetrics and is verified empirically by using two datasets from the Web of Science in the fields of electrochemistry and gerontology. For quantifying their relations, we estimate the g-index, ψ-index, and their cores and ratios of cores via a second-order Taylor series when the e-index, h-index, and C1 (the maximum number of citations received by a paper) are known. Then we find for the two empirical cases, that ratios of cores and average citations are approximately stable. Compared with the g-index, the offset-ability of the h-index decreases by 20% but the average citations increase by 20%. A similar observation holds for the comparison of the g-index and ψ-index. To explore the possible applications of cores of different indices, we apply them to extract the core structure of a network. The h-core is the most efficient, while the ψ-core includes more nodes with high betweenness. 相似文献
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Moy Patricia; Xenos Michael A.; Hess Verena K. 《Int. Journal of Public Opinion Research》2006,18(2):198-210
Having become fully integrated into the contemporary politicallandscape, infotainment-oriented media extend Americans’traditional news (e.g. newspaper, radio, and television) toinclude a greater number of sources for political information,and in some cases, political mobilization. Given the increasingprominence of infotainment-oriented media in contemporary politics,this study addresses the effects of one particular type of infotainment—late-nightcomedy—during the 2000 presidential campaign. Specifically,we are interested in whether watching late-night comedy showsinfluences viewers’ evaluations of the candidates whohave appeared on these shows; in particular, we investigatepriming as the mechanism by which such influences occur. Findingsfrom the 2000 National Annenberg Election Survey (N = 11,482)indicate that evaluations of candidates are based in part onrespondents’ sociodemographics, perceptions of candidatesto handle certain issues, and their character traits. Therewas a main effect of watching late-night comedy on evaluationsof candidates; more importantly, viewers were more likely thannonviewers to base their evaluations of George W. Bush on charactertraits after he appeared on The Late Show with David Letterman. 相似文献