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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   

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This paper presents the first meta-analysis of studies that computed correlations between the h index and variants of the h index (such as the g index; in total 37 different variants) that have been proposed and discussed in the literature. A high correlation between the h index and its variants would indicate that the h index variants hardly provide added information to the h index. This meta-analysis included 135 correlation coefficients from 32 studies. The studies were based on a total sample size of N = 9005; on average, each study had a sample size of n = 257. The results of a three-level cross-classified mixed-effects meta-analysis show a high correlation between the h index and its variants: Depending on the model, the mean correlation coefficient varies between .8 and .9. This means that there is redundancy between most of the h index variants and the h index. There is a statistically significant study-to-study variation of the correlation coefficients in the information they yield. The lowest correlation coefficients with the h index are found for the h index variants MII and m index. Hence, these h index variants make a non-redundant contribution to the h index.  相似文献   

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This paper reviews a number of studies comparing Thomson Scientific’s Web of Science (WoS) and Elsevier’s Scopus. It collates their journal coverage in an important medical subfield: oncology. It is found that all WoS-covered oncological journals (n = 126) are indexed in Scopus, but that Scopus covers many more journals (an additional n = 106). However, the latter group tends to have much lower impact factors than WoS covered journals. Among the top 25% of sources with the highest impact factors in Scopus, 94% is indexed in the WoS, and for the bottom 25% only 6%. In short, in oncology the WoS is a genuine subset of Scopus, and tends to cover the best journals from it in terms of citation impact per paper. Although Scopus covers 90% more oncological journals compared to WoS, the average Scopus-based impact factor for journals indexed by both databases is only 2.6% higher than that based on WoS data. Results reflect fundamental differences in coverage policies: the WoS based on Eugene Garfield’s concepts of covering a selective set of most frequently used (cited) journals; Scopus with broad coverage, more similar to large disciplinary literature databases. The paper also found that ‘classical’, WoS-based impact factors strongly correlate with a new, Scopus-based metric, SCImago Journal Rank (SJR), one of a series of new indicators founded on earlier work by Pinski and Narin [Pinski, G., & Narin F. (1976). Citation influence for journal aggregates of scientific publications: Theory, with application to the literature of physics. Information Processing and Management, 12, 297–312] that weight citations according to the prestige of the citing journal (Spearman’s rho = 0.93). Four lines of future research are proposed.  相似文献   

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This paper proposes an empirical analysis of several scientists based on their time regularity, defined as the ability of generating an active and stable research output over time, in terms of both quantity/publications and impact/citations. In particular, we empirically analyse three recent bibliometric tools to perform qualitative/quantitative evaluations under the new perspective of regularity. These tools are respectively (1) the PY/CY diagram, (2) the publication/citation Ferrers diagram and triad indicators, and (3) a year-by-year comparison of the scientists’ output (Borda's ranking). Results of the regularity analysis are then compared with those obtained under the classical perspective of overall production.The proposed evaluation tools can be applied to competitive examinations for research position/promotion, as complementary instruments to the commonly adopted bibliometric techniques.  相似文献   

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The Annual Reports of the Commissioner of Indian Affairs, for the years 1824 through 1920, described the interactions between the American Indian tribes and the federal government. J. A. Jones (Jones, J. A. (1955). Key to the annual reports of the Commissioner of Indian Affairs. Ethnohistory, 2, 58–64). Provided a key to these documents found in the United States Congressional Serial Set, but this tool contained a number of errors. This article provides a fresh look at this key, with particular focus upon the availability of these materials through the Readex Serial Set digital collection.  相似文献   

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