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1.
Antonio Quesada 《Journal of Informetrics》2009,3(2):158-160
The Hirsch index is a number that synthesizes a researcher's output. It is the maximum number h such that the researcher has h papers with at least h citations each. Woeginger [Woeginger, G. J. (2008a). An axiomatic characterization of the Hirsch-index. Mathematical Social Sciences, 56(2), 224–232; Woeginger, G. J. (2008b). A symmetry axiom for scientific impact indices. Journal of Informetrics, 2(3), 298–303] characterizes the Hirsch index when indices are assumed to be integer-valued. In this note, the Hirsch index is characterized, when indices are allowed to be real-valued, by adding to Woeginger's monotonicity two axioms in a way related to the concept of monotonicity. 相似文献
2.
Carlos Garcia-Zorita Ronald Rousseau Sergio Marugan-Lazaro Elias Sanz-Casado 《Journal of Informetrics》2018,12(3):567-578
Scientific journals are ordered by their impact factor while countries, institutions or researchers can be ranked by their scientific production, impact or by other simple or composite indicators as in the case of university rankings. In this paper, the theoretical framework proposed in Criado, R., Garcia, E., Pedroche, F. & Romance, M. (2013). A new method for comparing rankings through complex networks: Model and analysis of competitiveness of major European soccer leagues. Chaos, 23, 043114 for football competitions is used as a starting point to define a general index describing the dynamics or its opposite, stability, of rankings. Some characteristics to study rankings, ranking dynamics measures and axioms for such indices are presented. Furthermore, the notion of volatility of elements in rankings is introduced. Our study includes rankings with ties, entrants and leavers. Finally, some worked out examples are shown. 相似文献
3.
We propose two new indices that are able to measure a scientific researcher's overall influence and the level of his/her works’ association with the mainstream research subjects within a scientific field. These two new measures – the total influence index and the mainstream index – differ from traditional performance measures such as the simple citation count and the h-index in that they take into account the indirect influence of an author's work. Indirect influence describes a scientific publication's impact upon subsequent works that do not reference it directly. The two measures capture indirect influence information from the knowledge emanating paths embedded in the citation network of a target scientific field. We take the Hirsch index, data envelopment analysis, and lithium iron phosphate battery technology field to examine the characteristics of these two measures. The results show that the total influence index favors earlier researchers and successfully highlights those researchers who have made crucial contributions to the target scientific field. The mainstream index, in addition to underlining total influence, also spotlights active researchers who enter into a scientific field in a later development stage. In summary, these two new measures are valuable complements to traditional scientific performance measures. 相似文献
4.
Adrian Miroiu 《Journal of Informetrics》2013,7(1):10-15
Scientific impact indexes like h are responsive to two parameters: the researcher's productivity given by the number of her published papers (an aspect of quantity) and citations (an aspect of quality). In this paper I prove that the two parameters can be treated separately: the index h can be axiomatized by appealing (1) only to axioms that allow for productivity changes, but do not require taking into account distinct situations in which a researcher's papers received different numbers of citations or (2) only to axioms that allow for changes in the number of citations received by the researcher's papers, but do not require changes in scientific productivity. The axioms used are weak. Specifically, monotonicity is avoided. 相似文献
5.
Thomas R. Wagner 《Communication Research Reports》2018,35(4):346-355
This study’s goal was to learn how adding the extractive information-seeking behavior of Facebook profile viewing following face-to-face information-seeking behavior in initial interactions affected attributional confidence (AC) and social attraction (SA). Additionally, the present study was a quasi-replication of research exploring how changes in time spent on information seeking impacted AC and SA testing two uncertainty reduction theory axioms. Two modalities, face-to-face (FtF) only versus FtF and profile viewing, across three time conditions of 4, 6, and 8 minutes yielded six experimental conditions. AC for the two modalities were similar when time was held constant. Comparing the two modalities for 8 minutes resulted in higher social attraction for the FtF-only condition. Also, the data report a significant interaction with modality and time. Time impacts AC and SA even with relatively small changes. 相似文献
6.
《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
7.
László Csató 《Journal of Informetrics》2019,13(4):100975
Journal ranking is becoming more important in assessing the quality of academic research. Several indices have been suggested for this purpose, typically on the basis of a citation graph between the journals. We follow an axiomatic approach and find an impossibility theorem: any self-consistent ranking method, which satisfies a natural monotonicity property, should depend on the level of aggregation. Our result presents a trade-off between two axiomatic properties and reveals a dilemma of aggregation. 相似文献
8.
《Communication monographs》2012,79(3):303-332
The study of political mass communication information outlet effects has been dominated by two types of studies, those which focus on a single outlet and those which look at the comparative influence of multiple outlets. The current study seeks to advance a third study type by offering a theory of political campaign media connectedness. Three axioms are offered in this work. In addition, a series of hypotheses involving five political communication campaign information outlets (conservative political talk radio, FOX cable TV news, daily newspapers, national network TV news, debate viewing) are posited. This work emphasizes the need to understand how various information outlets function in coordination with one another to produce a potentially diverse set of direct and indirect political campaign media effects. Future lines of theoretical inquiry and empirical research are outlined. 相似文献
9.
期刊评价指标SJR、JIF和H指数的关系研究 总被引：4，自引：1，他引：3
10.
新媒介策略:“长尾”时代的双重博弈 总被引：4，自引：0，他引：4
本研究提出并回答三个问题:在新媒体时代,媒介融合的背后为何存在着媒体分化的反动?在受众对丰富信息要求的背后,是否隐藏着信息需求极简化的真相?如何理解这两组媒介策略之间的博弈?文章应用“长尾理论”,分析了以上两种策略博弈的经济理性,并指出了其均衡性所在。 相似文献
11.
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
12.
Antonio Quesada 《Journal of Informetrics》2011,5(3):476-480
The Hirsch index and the Egghe index are both numbers that synthesize a researcher's output. The h-index associated with researcher r is the maximum number h such that r has h papers with at least h citations each. The g-index is the maximum number g of papers by r such that the average number of citations of the g papers is at least g. Both indices are characterized in terms of four axioms. One identifies outputs deserving index at most one. A second one establishes a strong monotonicity condition. A third one requires the index to satisfy a property of subadditivity. The last one consists of a monotonicity condition, for the h-index, and an aggregate monotonicity condition, for the g-index. 相似文献
13.
《Library & information science research》1996,18(3):225-240
Library use and user satisfaction are multidimensional concepts. However, traditional methods of evaluation do not include appropriate global measures of these concepts. Two indices of library use and user satisfaction have been derived from a number of characteristics collected by means of a questionnaire that combined individual variable-scores and expressed them as a final score. One form of index was based on a simple approach producing a weighted sum of individual values scored for all surveyed items. The second form, based on the theory of factor analysis, especially the principal components procedure, highlighted the most important items defining either library use or user satisfaction. Thus, the indices verified the presence of any correlation between user satisfaction and library use and evaluated library activities and services at the libraries of the National University of Rwanda. They could be used to compare various libraries sharing the same baseline characteristics and profiles. 相似文献
14.
15.
Recently Woeginger [Woeginger, G. H. (2008-a). An axiomatic characterization for the Hirsch-index. Mathematical Social Sciences. An axiomatic analysis of Egghe's g-index. Journal of Informetrics] introduced a set of axioms for scientific impact measures. These lead to a characterization of the h-index. In this note we consider a slight generalization and check which of Woeginger's axioms are satisfied by the g-index, the h(2)-index and the R2-index. 相似文献
16.
Faramarz Soheili Ali Akbar Khasseh Afshin Mousavi Chelak Mohammad Tavakolizadeh‐Ravari 《Learned Publishing》2018,31(2):121-129
Influence and capital are two concepts used to evaluate scholarly outputs, and these can be measured using the Scholarly Capital Model as a modelling tool. The tool looks at the concepts of connectedness, venue representation, and ideational influence using centrality measures within a social network. This research used co‐authorships and h‐indices to investigate authors who have published papers in the field of information behaviour between 1980 and 2015 as extracted from Web of Science. The findings show a relationship between the authors’ connectedness and the venue (journal) representation. It could be seen that the venue (journal) influences the chance of citation, and equally, the prestige (centrality) of authors probably raises the citations of the journals. The research also shows a significant positive relationship between the venue representation and ideational influence. This means that a research work that is published in a highly cited journal will find more visibility and will receive more citations. 相似文献
17.
Marek Gagolewski 《Journal of Informetrics》2013,7(4):792-802
In this paper we deal with the problem of aggregating numeric sequences of arbitrary length that represent e.g. citation records of scientists. Impact functions are the aggregation operators that express as a single number not only the quality of individual publications, but also their author's productivity.We examine some fundamental properties of these aggregation tools. It turns out that each impact function which always gives indisputable valuations must necessarily be trivial. Moreover, it is shown that for any set of citation records in which none is dominated by the other, we may construct an impact function that gives any a priori-established authors’ ordering. Theoretically then, there is considerable room for manipulation in the hands of decision makers.We also discuss the differences between the impact function-based and the multicriteria decision making-based approach to scientific quality management, and study how the introduction of new properties of impact functions affects the assessment process. We argue that simple mathematical tools like the h- or g-index (as well as other bibliometric impact indices) may not necessarily be a good choice when it comes to assess scientific achievements. 相似文献
18.
Marek Kosmulski 《Journal of Informetrics》2012,6(4):611-614
Newly introduced bibliometric indices may be biased by the preference of scientists for bibliometric indices, in which their own research receives a high score. To test such a hypothesis, the publication and citation records of nine scientists who recently proposed new bibliometric indices were analyzed in terms of standard indicators, their own indicators, and indicators recently proposed by other scientists. The result of the test was negative, that is, newly introduced bibliometric indices did not favor their authors. 相似文献
19.
Simple Semantics in Topic Detection and Tracking 总被引：3，自引：0，他引：3
Topic Detection and Tracking (TDT) is a research initiative that aims at techniques to organize news documents in terms of news events. We propose a method that incorporates simple semantics into TDT by splitting the term space into groups of terms that have the meaning of the same type. Such a group can be associated with an external ontology. This ontology is used to determine the similarity of two terms in the given group. We extract proper names, locations, temporal expressions and normal terms into distinct sub-vectors of the document representation. Measuring the similarity of two documents is conducted by comparing a pair of their corresponding sub-vectors at a time. We use a simple perceptron to optimize the relative emphasis of each semantic class in the tracking and detection decisions. The results suggest that the spatial and the temporal similarity measures need to be improved. Especially the vagueness of spatial and temporal terms needs to be addressed. 相似文献
20.
在射影几何中,从对偶思想出发,研究“三点共线”与“三线共点”的结构形式,使得德萨格三角形定理及其对偶定理具有一．中“旋转”关系,进而给出这类问题求解的“规律性”方法。 相似文献