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Abstract  

According to the definition of reliability-based citation impact factor (R-impact factor) proposed by KUO & RUPE and the cumulative citation age distribution model, a mathematical expression of the relationship between R-impact factor and impact factor is established in this paper. By simulation of the change processes of the R-impact factor and impact factor in the manipulation process of the impact factor, it is found that the effect of manipulation can be partly corrected by the R-impact factor in some cases. Based on the Journal Citation Report database, impact factors of 4 normal journals and 4 manipulated journals were collected. The journals’ R-impact factors and self-cited rates in the previous two years were calculated for each year during the period 2000 to 2007, and various characteristics influenced by the manipulation were analyzed. We find that the R-impact factor has greater fairness than the impact factor for journals with relatively short cited half-lives. Finally, some issues about using the R-impact factor as a measure for evaluating scientific journals are discussed.

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Introduction J.K. Vanclay's 1 recent article Vanclay ( 2011 ) on the journal impact factor (JIF) is a new occasion to debate about the commander's statue in bibliometrics. The statue is still standing in spite of injuries from

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Introduction One of the most commonly used and prominent citation-based indicators of the performance and significance of a scientific journal is the journal impact factor (JIF), which was introduced in 1955 by Garfield ( 1999

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is 50 according to the Thomson Reuters Web of Science data base, and 58 according to the Google Scholar Universal Gadget. Journal impact factor (IF) Fifty years ago Eugene Garfield proposed the IF (Garfield 1972a , b

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Scientometrics
Authors:
Juan Miguel Campanario
,
Jesús Carretero
,
Vera Marangon
,
Antonio Molina
, and
Germán Ros

Introduction The journal impact factor (JIF) continues to be one of the most widely used scientometric indicators. It is computed for each year (Y) according to the following equation (Glänzel and Moed 2002 ): where Y1 and Y

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Abstract  

The ISI journal impact factor (JIF) is based on a sample that may represent half the whole-of-life citations to some journals, but a small fraction (<10%) of the citations accruing to other journals. This disproportionate sampling means that the JIF provides a misleading indication of the true impact of journals, biased in favour of journals that have a rapid rather than a prolonged impact. Many journals exhibit a consistent pattern of citation accrual from year to year, so it may be possible to adjust the JIF to provide a more reliable indication of a journal’s impact.

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Introduction As many have noted, the journal impact factor (JIF) may be the most widely used scientometric indicator. This indicator is computed for each year (Y) according to the following equation (Glänzel and Moed 2002

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There is some controversy around the impact factor (IF) rank-order distribution. The controversy is around the shape of the IF-rank-order distribution. In some articles (Lancho-Barrantes et al. 2010 ; Guerrero-Bote et al. 2007 ) one claims

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Abstract  

An examination of the relationships between journal impact factors and individual subscription prices of interdisciplinary social science journals revealed a very small and statistically nonsignificant negative association.

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Summary In a recent article Sombatsompop et al. (2004) proposed a new way of calculating a synchronous journal impact factor. Their proposal seems quite interesting and will be discussed in this note. Their index will be referred as the Median Impact Factor (MIF). I explain every step in detail so that readers with little mathematical background can understand and apply the procedure. Illustrations of the procedure are presented. Some attention is given to the estimation of the median cited age in case it is larger than ten year. I think the idea introduced by Sombatsompop, Markpin and Premkamolnetr has a great theoretical value as they are - to the best of my knowledge - the first ones to consider impact factors not using years as a basic ingredient, but an element of the actual form of the citation curve. The MIF is further generalized to the notion of a percentile impact factor.

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