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  • × author_ss:"Persson, O."
  1. Järvelin, K.; Persson, O.: ¬The DCI index : discounted cumulated impact-based research evaluation (2008) 0.03
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    Abstract
    Research evaluation is increasingly popular and important among research funding bodies and science policy makers. Various indicators have been proposed to evaluate the standing of individual scientists, institutions, journals, or countries. A simple and popular one among the indicators is the h-index, the Hirsch index (Hirsch 2005), which is an indicator for lifetime achievement of a scholar. Several other indicators have been proposed to complement or balance the h-index. However, these indicators have no conception of aging. The AR-index (Jin et al. 2007) incorporates aging but divides the received citation counts by the raw age of the publication. Consequently, the decay of a publication is very steep and insensitive to disciplinary differences. In addition, we believe that a publication becomes outdated only when it is no longer cited, not because of its age. Finally, all indicators treat citations as equally material when one might reasonably think that a citation from a heavily cited publication should weigh more than a citation froma non-cited or little-cited publication.We propose a new indicator, the Discounted Cumulated Impact (DCI) index, which devalues old citations in a smooth way. It rewards an author for receiving new citations even if the publication is old. Further, it allows weighting of the citations by the citation weight of the citing publication. DCI can be used to calculate research performance on the basis of the h-core of a scholar or any other publication data.
    Content
    Erratum in: Järvelin, K., O. Persson: The DCI-index: discounted cumulated impact-based research evaluation. Erratum re. In: Journal of the American Society for Information Science and Technology. 59(2008) no.14, S.2350-2352.
    Object
    DCI index
  2. Järvelin, K.; Persson, O.: ¬The DCI-index : discounted cumulated impact-based research evaluation (2008) 0.03
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    Abstract
    The article by K. Järvelin & O. Persson published in JASIST 59(9), The DCI-Index: Discounted Cumulated Impact-Based Research Evaluation, (pp. 1433-1440) contains an unfortunate error in one of its formulas, Equation 3. The present paper gives the correction and an example of impact analysis based on the corrected formula.
    Object
    h-index
  3. Persson, O.; Melin, G.: Equalization, growth and integration of science (1996) 0.02
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    Abstract
    Presents a study of the production of scientific papers, coauthorships and R&D expenditures in the OECD countries. Discusses the distribution of papers in the journal 'Science' by OECD country in comparison with 'Science Citation Index' papers as a whole and compares these to the distribution of R&D investments
  4. Melin, G.; Persson, O.: Hotel cosmopolitan : a bibliometric study of collaboration at some European universities (1998) 0.02
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    Abstract
    The collaborative pattern of all Nordic universities, as well as a few universities in the UK and the Netherlands, is analyzed using institutionally co-authored articles retrieved from Science Citation Index. The study shows that there are no major differences between universities of various size when it comes to the proportion of articles with internal, national, or international co-authorships. There are some country variations, but within each country, the differences among the universities are small, if any. When co-authorships were fractionalized according to the number of times a given university occurs among the addresses of an article, there were still no significant differences between universities of varying size. Since external collaboration, whether it is national or international, accounts for more than half of all articles produced by the universities, one is inclined to conclude that the universities function as a kind of cosmopolitan hotel housing nodes of scientific networks that are becoming increasingly international
    Aid
    Science Citation Index
  5. Persson, O.; Beckmann, M.: Locating the network of interacting authors in scientific specialities (1995) 0.02
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    Abstract
    Seeks to describe the social networks, or invisible colleges, that make up a scientific speciality, in terms of mathematically precise sets generated by document citations and accessible through the Social Science Citation Index. The document and author sets that encompass a scientific specialty are the basis for some interdependent citation matrices. The method of construction of these sets and matrices is illustrated through an application to the literature on invisible colleges
  6. Leydesdorff, L.; Persson, O.: Mapping the geography of science : distribution patterns and networks of relations among cities and institutes (2010) 0.01
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    Object
    Science Citation Index