Search (6 results, page 1 of 1)

0.10606643 = product of:
  0.15909964 = sum of:
    0.08515447 = weight(_text_:citation in 2717) [ClassicSimilarity], result of:
      0.08515447 = score(doc=2717,freq=2.0), product of:
        0.23479973 = queryWeight, product of:
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.050071523 = queryNorm
        0.3626685 = fieldWeight in 2717, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.0546875 = fieldNorm(doc=2717)
    0.073945165 = product of:
      0.14789033 = sum of:
        0.14789033 = weight(_text_:index in 2717) [ClassicSimilarity], result of:
          0.14789033 = score(doc=2717,freq=8.0), product of:
            0.21880072 = queryWeight, product of:
              4.369764 = idf(docFreq=1520, maxDocs=44218)
              0.050071523 = queryNorm
            0.67591333 = fieldWeight in 2717, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              4.369764 = idf(docFreq=1520, maxDocs=44218)
              0.0546875 = fieldNorm(doc=2717)
      0.5 = coord(1/2)
  0.6666667 = coord(2/3)

Abstract

Temporal growth of the h-index in a diachronous cumulative time series is predicted to be linear by Hirsch (2005), whereas other models predict a concave increase. Actual data generally yield a linear growth or S-shaped growth. We study the h-index's growth in computer simulations of the publication-citation process. In most simulations the h-index grows linearly in time. Only occasionally does an S-shape occur, while in our simulations a concave increase is very rare. The latter is often signalled by the occurrence of plateaus - periods of h-index stagnation. Several parameters and their influence on the h-index's growth are determined and discussed.

0.045336 = product of:
  0.136008 = sum of:
    0.136008 = weight(_text_:citation in 2037) [ClassicSimilarity], result of:
      0.136008 = score(doc=2037,freq=10.0), product of:
        0.23479973 = queryWeight, product of:
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.050071523 = queryNorm
        0.57925105 = fieldWeight in 2037, product of:
          3.1622777 = tf(freq=10.0), with freq of:
            10.0 = termFreq=10.0
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2037)
  0.33333334 = coord(1/3)

Abstract

This is a publisher ranking study based on a citation data grant from Elsevier, specifically, book titles cited in Scopus history journals (2007-2011) and matching metadata from WorldCat® (i.e., OCLC numbers, ISBN codes, publisher records, and library holding counts). Using both resources, we have created a unique relational database designed to compare citation counts to books with international library holdings or libcitations for scholarly book publishers. First, we construct a ranking of the top 500 publishers and explore descriptive statistics at the level of publisher type (university, commercial, other) and country of origin. We then identify the top 50 university presses and commercial houses based on total citations and mean citations per book (CPB). In a third analysis, we present a map of directed citation links between journals and book publishers. American and British presses/publishing houses tend to dominate the work of library collection managers and citing scholars; however, a number of specialist publishers from Europe are included. Distinct clusters from the directed citation map indicate a certain degree of regionalism and subject specialization, where some journals produced in languages other than English tend to cite books published by the same parent press. Bibliometric rankings convey only a small part of how the actual structure of the publishing field has evolved; hence, challenges lie ahead for developers of new citation indices for books and bibliometricians interested in measuring book and publisher impacts.

0.020274874 = product of:
  0.06082462 = sum of:
    0.06082462 = weight(_text_:citation in 398) [ClassicSimilarity], result of:
      0.06082462 = score(doc=398,freq=2.0), product of:
        0.23479973 = queryWeight, product of:
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.050071523 = queryNorm
        0.25904894 = fieldWeight in 398, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.0390625 = fieldNorm(doc=398)
  0.33333334 = coord(1/3)

Abstract

Purpose - The aim of this paper is to propose a conceptual model of the field of informetrics. Specifically, the paper argues that informetrics comprises the study of entities in three dimensions: the social, documentary and epistemic dimensions containing respectively agents, documents, and concepts or cognitions. Design/methodology/approach - The paper outlines a conceptual model, drawing on earlier work by Kochen, Leydesdorff, Borgman and others. Subsequently, each dimension and interdimensional relation is analyzed and discussed. Findings - It is shown that not every study necessarily involves each of the three dimensions, but that the field as a whole cannot be reduced to one or two of them. Moreover, the dimensions should be kept separate but they are not completely independent. The paper discusses what kinds of relations exist between the dimensions. Special attention is given to the nature of the citation relation within this framework. The paper also considers the place of concepts like mapping, proximity and influence in the model. Research limitations/implications - This conceptual paper is a first step. Multi-relational networks may be a key instrument to further the study of the interplay between the three dimensions. Originality/value - The paper provides a framework to characterise informetric studies and makes the characteristics of the field explicit.

0.020274874 = product of:
  0.06082462 = sum of:
    0.06082462 = weight(_text_:citation in 5226) [ClassicSimilarity], result of:
      0.06082462 = score(doc=5226,freq=2.0), product of:
        0.23479973 = queryWeight, product of:
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.050071523 = queryNorm
        0.25904894 = fieldWeight in 5226, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          4.6892867 = idf(docFreq=1104, maxDocs=44218)
          0.0390625 = fieldNorm(doc=5226)
  0.33333334 = coord(1/3)

Abstract

Aims to inform researchers about metrics so that they become aware of the evaluative techniques being applied to their scientific output. Understanding these concepts will help them during their funding initiatives, and in hiring and tenure. The book not only describes what indicators do (or are designed to do, which is not always the same thing), but also gives precise mathematical formulae so that indicators can be properly understood and evaluated. Metrics have become a critical issue in science, with widespread international discussion taking place on the subject across scientific journals and organizations. As researchers should know the publication-citation context, the mathematical formulae of indicators being used by evaluating committees and their consequences, and how such indicators might be misused, this book provides an ideal tome on the topic. Provides researchers with a detailed understanding of bibliometric indicators and their applications. Empowers researchers looking to understand the indicators relevant to their work and careers. Presents an informed and rounded picture of bibliometrics, including the strengths and shortcomings of particular indicators. Supplies the mathematics behind bibliometric indicators so they can be properly understood. Written by authors with longstanding expertise who are considered global leaders in the field of bibliometrics

0.01493918 = product of:
  0.044817537 = sum of:
    0.044817537 = product of:
      0.089635074 = sum of:
        0.089635074 = weight(_text_:index in 4994) [ClassicSimilarity], result of:
          0.089635074 = score(doc=4994,freq=4.0), product of:
            0.21880072 = queryWeight, product of:
              4.369764 = idf(docFreq=1520, maxDocs=44218)
              0.050071523 = queryNorm
            0.40966535 = fieldWeight in 4994, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              4.369764 = idf(docFreq=1520, maxDocs=44218)
              0.046875 = fieldNorm(doc=4994)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)

Abstract

Contrary to what one might expect, Nobel laureates and Fields medalists have a rather large fraction (10% or more) of uncited publications. This is the case for (in total) 75 examined researchers from the fields of mathematics (Fields medalists), physics, chemistry, and physiology or medicine (Nobel laureates). We study several indicators for these researchers, including the h-index, total number of publications, average number of citations per publication, the number (and fraction) of uncited publications, and their interrelations. The most remarkable result is a positive correlation between the h-index and the number of uncited articles. We also present a Lotkaian model, which partially explains the empirically found regularities.

0.011306668 = product of:
  0.03392 = sum of:
    0.03392 = product of:
      0.06784 = sum of:
        0.06784 = weight(_text_:22 in 4992) [ClassicSimilarity], result of:
          0.06784 = score(doc=4992,freq=2.0), product of:
            0.17534193 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.050071523 = queryNorm
            0.38690117 = fieldWeight in 4992, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.078125 = fieldNorm(doc=4992)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)

Date

14. 2.2012 12:53:22