oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Theoretical difference between impact factor and influence factor
?ilda Pe?ari?,Miroslav Tu?man
Journal of Information and Organizational Sciences , 2010,
Abstract: Bibliometric constructions of "knowledge maps" and "cognitive structures of science" do not differentiate between impact and influence factors. The difference can be constructedaccording to different meaning and interpretation of the terms reference and citation. Reference is "acknowledgment which one author gives to another", whereas citation is "acknowledgment which one document receives from another". Development of Information Science according to period and subject area is analyzed on the corpus of citation literature retrieved from doctoral dissertations in Information Science from 1978 to 2007 at Croatian universities. The research aim is to indicate the difference between document impact factor and author's influence factor (i.e. reference ability to produce effects on actions, behavior, and opinions of authors of doctoral theses). The influence factor serves to distinguish the key role of cited authors in time and according to the duration of the influence (the average age for cited papers of dominant authors in different periods is between eight and ten years). The difference between linear and interactive communication seems vital for the interpretation of cited half-life, i.e. the attitude of one science community towards used information resources and cognitive heritage. The analyzed corpus of 22,210 citations can be divided into three communication phases according to influence factor criteria: in the phase of dialogue and interactive communication 25% of bibliographic units are cited in the first four years; in the second phase another 25% of units are cited from the fifth to the ninth year; after ten years, in the dominant linear communication phase, approximately 30% of units are cited.
Impact Factor : Pros and Cons
Javed Ali,Alka ahuja,Sanjula Baboota,R. K. Khar
Pharmaceutical Reviews , 2003,
Abstract: In recent years the Institute of Scientific Information Journal Citation Reports impact factor has changed from an obscure bibliometric indicator to become the chief quantitative measure of the quality of a journal, its published papers, the scientists who wrote those papers and even the institutes they work within. This article looks at the use and abuse of the impact factor, how it should and should not be used. Introduction The impact factor is o-ne of the three standardized measures created by the Institute of Scientific Information (ISI) which can be used to measure the way a journal receives citations to its articles over time (1,2). These characteristics form the basis of the ISI indicators impact factor, immediacy index and cited half-life. The journal impact factor is a measure of the frequency with which the "average article" in a journal has been cited in a particular year. The impact factor will help you evaluate a journal’s relative importance, especially when you compare it to others in the same field. The impact factor is calculated by dividing the number of current citations to articles published in the two previous years by the total number of articles published in that period. The impact factor is useful in clarifying the significance of absolute (or total) citation frequencies. It eliminates some of the bias of such counts which favour large journals over small o-nes, or frequently issued journals over less frequently issued o-nes, and of older journals over newer o-nes. In the latter case such journals have a larger citable body of literature than smaller or younger journals (3,4).
Factor de impacto Impact factor  [cached]
óscar Alfredo Beltrán Galvis
Revista Colombiana de Gastroenterologia , 2006,
Abstract: El Factor de Impacto es un índice bibliométrico utilizado para medir la calidad de las revistas y de los artículos, pero tiene limitaciones, y no puede ser el único. No se debe sobrevalorar la cantidad de veces que, por distintas circunstancias, ha sido citado un artículo, sin medir la real calidad de la investigación o del trabajo. The Impact factor is a scientometric indicator utilized to measure the quality of the journals and papers. But, it has limitations, and cannot be the only one. Itself not the quantity of times should be overrated, that by different circumstances, has been cited a paper, without measuring the real quality of the investigation.
Bias in the journal impact factor  [PDF]
Jerome K Vanclay
Computer Science , 2006, DOI: 10.1007/s11192-008-1778-4
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.
The Impact of Structure and Meaning in Reading Comprehension Among Gifted Students  [PDF]
Emad M. AL-Salameh,Ayed H. Ziadat,Madher M. Attiat
Journal of Applied Sciences , 2010,
Abstract: The aim of this study was to evaluate the impact of structure (passive and active), meaning (known and unknown) of reading and comprehension at both levels of literal and interpretative among gifted students. A sample of (160) gifted individuals were selected. Students were divided into four experimental groups. Materials from a tenth grade text book was chosen and modified as sentences of (passive and active voice statements), in addition to the meaning of (commonly used and not commonly used vocabularies) were applied, further modification between the two variables applied in which all possibilities were included. The results of this study indicated that: statistical significant values were present in the understanding of reading both literal and interpretive of the passive voice sentences among gifted individuals. Also, a statistical significant indication was evident in the binary interaction of sentences built from the true meanings and the structure complexity of sentences. On the other hand, no statistical significant differences were found among gifted students on the level of literally understanding and interpretation. Also no statistical significant was found between the binary interaction of the structure of the sentences and the direct meaning of such sentences among the groups of gifted students.
Having an impact (factor)
Gregory A Petsko
Genome Biology , 2008, DOI: 10.1186/gb-2008-9-7-107
Abstract: The place: The entrance to The Pearly Gates. There are fluffy clouds everywhere. In the center is a podium with an enormous open book. A tall figure in white robes with white hair and beard stands at the podium. Approaching is a thin, middle-aged man with glasses and a bewildered expression. He is the soul of a recently deceased genome biologist.GB: My gosh is this...? Are you...? Am I really...?St Peter: Yes, I'm St Peter. And yes, this is where souls such as yours enter heaven.GB: Wow. I mean, I didn't expect to live forever, but still, this is something of a shock. (Pauses.) OK, I guess I can live with it. Uh, I mean ...St Peter: I know.GB: Well, at least I'm here. I'm not thrilled to be dead, but it's a relief to know I'm going to heaven.St Peter: I'm afraid it's not that simple. We have to check.GB: Check what?St Peter: Your life history. (He leafs through the enormous book.) It's all here, you know.GB: I'm sure it is. I can imagine you guys keep records that make PubMed seem like a stack of index cards. I'm a little surprised you don't use something more up-to-date, though.St Peter: If you mean a personal computer, no - we don't. After all, they were invented elsewhere.GB: You mean on earth?St Peter: No, somewhere a lot warmer. (He stops at a page.) Here you are.GB: Hey, I'm not worried. I was a good scientist, a good citizen, a good family man, I think, too. I never...St Peter: Yes, yes, I'm sure, but you see, none of that matters. The only thing that matters is your IF.GB: IF?St Peter: Your impact factor. That's all we use now. If your IF is above 10, then you enter here. If it's lower, well...GB: My impact factor? What the hell - oops, sorry - is that?St Peter: It's something we borrowed from you science chaps on earth. Oh, we used to do it the hard way: send a fledgling angel down to check on your deeds; look at how your life affected your friends and family, consider your intentions versus your actions. All that sort of thing. It was tedious and required
Impactitis: The impact factor myth syndrome  [cached]
Elsaie Mohamed,Kammer Jenna
Indian Journal of Dermatology , 2009,
Abstract: Background : In the early 1960s, Eugene Garfield and Irving Sher created the journal impact factor to help select journals for the Science Citation Index (SCI). Today it has become a widespread subject of controversy even for Garfield, the man who created it who is quoted saying " Impact Factor is not a perfect tool to measure the quality of articles but there is nothing better and it has the advantage of already being in existence and is, therefore, a good technique for scientific evaluation". The use of the term "impact factor" has gradually evolved, especially in Europe, to include both journal and author impact. This ambiguity often causes problems. It is one thing to use impact factors to compare journals and quite another to use them to compare authors. Journal impact factors generally involve relatively large populations of articles and citations. Individual authors, on average, produce much smaller numbers of articles. Objectives: Impact factor, an index based on the frequency with which a journal′s articles are cited in scientific publications, is a putative marker of journal quality. However, empiric studies on impact factor′s validity as an indicator of quality are lacking. The authors try to evaluate and highlight the validity of Impact Factors and its significance as a tool of assessment for scientific publications. Methods: Analysis of the several reports in literature and from their own point of view. Conclusion: A journal′s impact factor is based on 2 elements: the numerator, which is the number of citations in the current year to any items published in a journal in the previous 2 years, and the denominator, which is the number of substantive articles (source items) published in the same 2 years. The impact factor could just as easily be based on the previous year′s articles alone, which would give an even greater weight to rapidly changing fields.
What are scientific leaders? The introduction of a normalized impact factor  [PDF]
George E. A. Matsas
Physics , 2008,
Abstract: We define a normalized impact factor suitable to assess in a simple way both the strength of scientific communities and the research influence of individuals. We define those ones with $NIF \geq 1$ as being scientific leaders since they would influence their peers at least as much as they are influenced by them. The NIF is distinguished because (a) this has a clear and universal meaning being applicable with equal efficiency to individuals belonging to scientific communities with quite different publication and citation traditions and (b) this is robust against self-citation expedient. This is eventually applied to a community derived from the list of outstanding referees recognized by the American Physical Society in 2008.
El factor de impacto Impact Factor
Natalia González Delgado
Revista Colombiana de Psiquiatría , 2010,
Abstract: Introducción: La tendencia a evaluar las revistas de la literatura científica y biomédica existe desde hace aproximadamente 80 a os, tiempo durante el cual los métodos para ello han ido cambiando, hasta llegar a lo que hoy se conoce como el factor de impacto, una medida del número promedio de veces en las cuales los trabajos publicados son citados hasta dos a os después de su publicación. Objetivo: Mostrar cómo ha sido la historia del factor de impacto, su definición y su papel dentro del campo de la investigación, así como la controversia que ha generado, y lo relacionado con el uso y el abuso que se le ha dado. Método: Revisión narrativa sobre el tema. Desarrollo: Creado en 1960 por Irving H. Sher y Eugene Garfield, anualmente la Revista de Reporte de Citaciones (Journal Citation Report [JCR]), del Instituto Thomson Reuters, ofrece una serie de herramientas para evaluar el factor de impacto. Así, el de una revista para el 2009 es igual a A/B. Donde A es el número de veces que los artículos publicados en los a os 2007 y 2008 fueron citados en revistas indexadas durante el a o 2009 y B es el número de artículos publicados entre 2007 y 2008 Introduction: The evaluation of medical and scientific journals during the past 80 years has been an important tendency in research. During this time evaluation methods have changed, arriving to what is known today as the impact factor. Objective: To show the impact factor's history, its definition and its role within the field of research, as well as the controversy it has generated in relation to its use vs. abuse. Method: Narrative review. Development: The impact factor was created in 1960 by Irving H. Sher and Eugene Garfield, and is published annually in the Journal of Citation Report (JCR) of the Thomson Reuters Institute, which offers a range of tools for its assessment. It is a measure of the average number of times published papers are cited up to two years after publication. Thus the impact factor 2009 for a journal is equal to A/B, where A is the number of times articles published in 2007- 2008 were cited in indexed journals during 2009, and B the number of articles published in 2007-2008
Reliability of journal impact factor rankings
Darren C Greenwood
BMC Medical Research Methodology , 2007, DOI: 10.1186/1471-2288-7-48
Abstract: Based on citations to journals in research and experimental medicine in 2005, Bayesian Markov chain Monte Carlo methods were used to estimate the uncertainty associated with these journal performance indicators.Intervals representing plausible ranges of values for journal impact factor ranks indicated that most journals cannot be ranked with great precision. Only the top and bottom few journals could place any confidence in their rank position. Intervals were wider and overlapping for most journals.Decisions placed on journal impact factors are potentially misleading where the uncertainty associated with the measure is ignored. This article proposes that caution should be exercised in the interpretation of journal impact factors and their ranks, and specifically that a measure of uncertainty should be routinely presented alongside the point estimate.Journal citation reports are used widely as the basis for assessing research output. They are used by funding bodies to gauge the quality of publications, by researchers to assess which journals they choose to submit manuscripts to, and as a basis for journals to attract new subscriptions and advertising [1]. In addition, current discussion surrounding the future nature of the UK Research Assessment Exercise (RAE) involves greater use of such bibliometric data [2,3]. The journal impact factor is the most widely cited bibliometric tool used to characterise journals. It was originally proposed 50 years ago as a measure of the impact that individual articles have on the research community [4], but it is now more commonly used across all articles published by a journal to provide a measure of a journal's impact on the research community rather than the impact of an individual article [5]. The journal impact factor is thus calculated as the number of citations a journal has received in the last complete year for articles published in the two preceding years, divided by the total number of articles the journal published in the
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.