چکیده:
The increasing number of scientific journals, even in a subfield,
necessitates a reliable and authoritative measure for researchers and
libraries to identify core journals in a given subfield. The impact factor
value is affected by different factors such as subject area, type of
documents or length of the citation measurement window. In order to
prioritize the choice of quality journals for scientists and libraries two
new measures (Indices) have been developed. The DSI is an aid to
decision-making with regards to the level of journal specialism within a
particular discipline and serves to inform researchers in the field who
wish to make individual subscription decisions. DPI has been proposed as
a decision-making tool for libraries as it indicates the proportion of all
citations within a particular discipline that have been received by a
particular journal.
خلاصه ماشینی:
Citation Introduction The Impact Factors, as introduced by Garfield (1979), of about 7500 scientific journals in different specialized disciplines are readily available through the ISI.
The Cited Half-Life Impact Factor (CHAL-IF) of Sombatsompop, Markpin, Yochai & Saechiew (2004) is based on replacing the two-year citation window with the journal's cited half-life in the IF computation formula.
Similarly, the same problem was approached by Sombatsompop, Markpin, Yochai & Saechiew (2005) who introduced a new mathematical index, the "Impact Factor Point Average" with the specific aim to allow across-field comparison of IF.
Whilst the number of citations received per article is a readily available measure, it does not provide any discipline-specific information that would allow the librarian to determine which of the journals within the field of e.
Utilizing Garfield's Impact factor measure assumes that the citations received by a journal relate directly to its specialist discipline.
Table 1 shows the Impact factor of these Journals based on the number of articles and the number of citations received.
Similarly, the number of citations received by a journal can be considered to be its level of influence, whilst the impact factor is similar to the per capita GDP, indicating the average number of citations per article.
Development of Two Proposed Alternative Measures for Intra-Disciplinary Comparisons The limitation of Garfield Impact Factor (GIF) being addressed in this study is in relation to the field of investigation (discipline) that is the main focus of an article.