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Starting from the notion of h-type indices for infinite sequences we investigate if these indices satisfy natural inequalities related to the arithmetic, the geometric and the harmonic mean. If f denotes an h-type index, such as the h- or the g-index, then we investigate inequalities such as min(f(X),f(Y)) ≤ f((X?+?Y)/2) ≤ max(f(X), f(Y)). We further investigate if: f(min(X,Y)) = min(f(X),f(Y)) and if f(max(X,Y)) = max(f(X),f(Y)). It is shown that the h-index satisfies all the equalities and inequalities we investigate but the g-index does not always, while it is always possible to find a counterexample involving the R-index. This shows that the h-index enjoys a number of interesting mathematical properties as an operator in the partially ordered positive cone (R+)∞ of all infinite sequences with non-negative real values.In a second part we consider decreasing vectors X and Y with components at most at distance d. Denoting by D the constant sequence (d,d,d, …) and by Y-D the vector (max(yr-d), 0)r, we prove that under certain natural conditions, the double inequality h(Y-D) ≤ h(X) ≤ h(Y?+?D) holds. 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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《Journal of Informetrics》2019,13(3):785-792
In this article we solve a minimum problem involving step functions. The solution of this problem leads to an investigation into generalized h- and g-indices. This minimum problem and the related generalized h- and g-indices are studied in a general context of decreasing differentiable functions as well as in the specific case of Lotkaian informetrics. The study illustrates the use of h-and g-indices and their generalizations in a context which bears no relation to the research evaluation context in which these indices were originally introduced. 相似文献
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The purpose of this article is to come up with a valid categorization and to examine the performance and properties of a wide range of h-type indices presented recently in the relevant literature. By exploratory factor analysis (EFA) we study the relationship between the h-index, its variants, and some standard bibliometric indicators of 26 physicists compiled from the Science Citation Index in the Web of Science. 相似文献
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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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结合中国引文数据库和W eb of Science数据库,利用h指数及类h指数,提出加权平均(h,g,R)指数,对我国大学图书馆的学术影响力进行评价;利用元h指数及类元h指数,提出元加权平均(h,g,R)指数,对图书馆作者群体学术影响力进行评价。研究作者群体学术影响力与图书馆学术影响力之间的关系,结合作者群体的h指数分布,分析不同作者群体对图书馆学术研究的影响模式。认为加权平均(h,g,R)指数及元加权平均(h,g,R)指数对图书馆和作者群学术影响力的评价更合理,作者群体学术影响力与图书馆学术影响力高度相关。 相似文献
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Marek Kosmulski 《Journal of Informetrics》2013,7(2):313-317
Standard bibliometric indices were re-defined using a generalized concept of “successful paper”. A family-tree based upon the new definitions provides new insights into the relationships between the standard indices, and empty boxes in the family-tree may inspire design of new indices. 相似文献
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Michael Schreiber 《Journal of Informetrics》2010,4(4):647-651
The Hirsch index h and the g index proposed by Egghe as well as the f index and the t index proposed by Tol are shown to be special cases of a family of Hirsch index variants, based on the generalized mean with exponent p. Inequalities between the different indices are derived from the generalized mean inequality. The graphical determination of the indices is shown for one example. 相似文献
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This paper proposes a new node centrality measurement index (c-index) and its derivative indexes (iterative c-index and cg-index) to measure the collaboration competence of a node in a weighted network. We prove that c-index observe the power law distribution in the weighted scale-free network. A case study of a very large scientific collaboration network indicates that the indexes proposed in this paper are different from other common centrality measures (degree centrality, betweenness centrality, closeness centrality, eigenvector centrality and node strength) and other h-type indexes (lobby-index, w-lobby index and h-degree). The c-index and its derivative indexes proposed in this paper comprehensively utilize the amount of nodes’ neighbors, link strengths and centrality information of neighbor nodes to measure the centrality of a node, composing a new unique centrality measure for collaborative competency. 相似文献
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本文根据ISBD(CM)、AACR_2和《测绘图资料:AACR_2阐释手册》(Cartographic Materials:a Manual of Interpretation for AACR_2),对地图和天图的坐标及其相关著录单元的著录方法做了详细讲解,并指出《地图资料著录规则》的某些规则与ISBD(CM)不符,而且规定不尽合理。 相似文献
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This article reviews a new variant of the generalized JSM-method for automatic support of scientific research (ASRS). This version of the JSM-method applied for ASRS contains ternary predicates of similarity (cause, brake, effect) which contain binary “cause–effect” predicates and explicit brake definitions. The article considers a possibility for the basis of fact partition for the cases of the truth of the generalized method and an inductive method of similarity with a ban on counter-example predicates. 相似文献
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《Journal of Informetrics》2014,8(2):384-389
We show mathematically that the success-index can be any of the following impact indices, dependent on the value of the threshold used in the definition of the success-index: Hirsch-index (h-index), g-index, generalized Wu- and Kosmulski-indices, the average. 相似文献
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《Journal of Government Information》1998,25(4):331-351
This article examines the forces that have made federal scientific publication an essentially private enterprise. Particular attention is paid to the rise of the scientific community in the American political system. The period under review begins roughly with 1941 and American involvement in World War II, which coincides with the establishment of the Office of Scientific Research and Development (ORSD). The article examines OSRD’s method of conducting federal scientific research, its contractual system, and the new publishing paradigm that it engendered. The article concludes in the 1960s with congressional efforts to revise provisions in Title 17, the 相似文献
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文章首先分析了个人对人事档案享有何种权利,认为个人对其人事档案享有的权利不能视为物权、个人对其人事档案享有的权利本质上是一种信息维护权;其次对个人人事档案遗失应当如何救济提出了自己的观点。 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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一种面向图书馆新书推荐服务的广义关联规则挖掘算法 总被引：1，自引：0，他引：1
基于MMS_Cumulate和GP-Apriori算法, 提出一种针对图书馆新书推荐服务特点的广义关联规则挖掘算法MAR_LCR。不仅能挖掘出形如“读者-图书”的广义关联规则,而且还允许用户为不同的项设置不同的最小支持度。通过对候选集的产生过程进行改进,可大大压缩搜索空间。实验结果表明,MAR_LCR算法是有效的。最后,提出新书推荐模型。 相似文献