1,345 research outputs found
Generalized h-index for Disclosing Latent Facts in Citation Networks
What is the value of a scientist and its impact upon the scientific thinking?
How can we measure the prestige of a journal or of a conference? The evaluation
of the scientific work of a scientist and the estimation of the quality of a
journal or conference has long attracted significant interest, due to the
benefits from obtaining an unbiased and fair criterion. Although it appears to
be simple, defining a quality metric is not an easy task. To overcome the
disadvantages of the present metrics used for ranking scientists and journals,
J.E. Hirsch proposed a pioneering metric, the now famous h-index. In this
article, we demonstrate several inefficiencies of this index and develop a pair
of generalizations and effective variants of it to deal with scientist ranking
and with publication forum ranking. The new citation indices are able to
disclose trendsetters in scientific research, as well as researchers that
constantly shape their field with their influential work, no matter how old
they are. We exhibit the effectiveness and the benefits of the new indices to
unfold the full potential of the h-index, with extensive experimental results
obtained from DBLP, a widely known on-line digital library.Comment: 19 pages, 17 tables, 27 figure
Zipf's law and log-normal distributions in measures of scientific output across fields and institutions: 40 years of Slovenia's research as an example
Slovenia's Current Research Information System (SICRIS) currently hosts
86,443 publications with citation data from 8,359 researchers working on the
whole plethora of social and natural sciences from 1970 till present. Using
these data, we show that the citation distributions derived from individual
publications have Zipfian properties in that they can be fitted by a power law
, with between 2.4 and 3.1 depending on the
institution and field of research. Distributions of indexes that quantify the
success of researchers rather than individual publications, on the other hand,
cannot be associated with a power law. We find that for Egghe's g-index and
Hirsch's h-index the log-normal form
applies best, with and depending moderately on the underlying set of
researchers. In special cases, particularly for institutions with a strongly
hierarchical constitution and research fields with high self-citation rates,
exponential distributions can be observed as well. Both indexes yield
distributions with equivalent statistical properties, which is a strong
indicator for their consistency and logical connectedness. At the same time,
differences in the assessment of citation histories of individual researchers
strengthen their importance for properly evaluating the quality and impact of
scientific output.Comment: 8 pages, 3 figures; accepted for publication in Journal of
Informetrics [supplementary material available at
http://www.matjazperc.com/sicris/stats.html
Applying weighted PageRank to author citation networks
This paper aims to identify whether different weighted PageRank algorithms
can be applied to author citation networks to measure the popularity and
prestige of a scholar from a citation perspective. Information Retrieval (IR)
was selected as a test field and data from 1956-2008 were collected from Web of
Science (WOS). Weighted PageRank with citation and publication as weighted
vectors were calculated on author citation networks. The results indicate that
both popularity rank and prestige rank were highly correlated with the weighted
PageRank. Principal Component Analysis (PCA) was conducted to detect
relationships among these different measures. For capturing prize winners
within the IR field, prestige rank outperformed all the other measures.Comment: 19 pages, 4 figures, 5 table
On the time dependence of the -index
The time dependence of the -index is analyzed by considering the average
behaviour of as a function of the academic age for about 1400 Italian
physicists, with career lengths spanning from 3 to 46 years. The individual
-index is strongly correlated with the square root of the total citations
: . For academic ages ranging from 12 to 24
years, the distribution of the time scaled index is
approximately time-independent and it is well described by the Gompertz
function. The time scaled index has an average approximately
equal to 3.8 and a standard deviation approximately equal to 1.6. Finally, the
time scaled index appears to be strongly correlated with the
contemporary -index
Development G-Index and H-Index : Dgh-Index
Of the most important indicators such as the h-index ,a method of measuring the productivity and impact of an academic's work, is often used as a component or metric in the ranking of higher education institutions and their staff then proposed the g index as a modification of the h index. So the g-index, have been Trying to develop and improve the disadvantage in h-index. and although the g-index can provide a more comprehensive measure of scientific contribution, but value g-index is integer where two authors or more than may be get the same g-index value although different number of citations and papers, making it difficult to differentiate performance between authors so in paper we suggest improvement index to resolve this problem is called dgh-index that gives new features to g-index and h-index that give us real number not an integer
The w-index: A significant improvement of the h-index
I propose a new measure, the w-index, as a particularly simple and useful way
to assess the integrated impact of a researcher's work, especially his or her
excellent papers. The w-index can be defined as follows: If w of a researcher's
papers have at least 10w citations each and the other papers have fewer than
10(w+1) citations, his/her w-index is w. It is a significant improvement of the
h-index.Comment: 7 pages, 3 tables, small changes from v
- …