Keywords: researcher index, citation index, publications
Biomedicine and Biotechnology, 2013 1 (2),
pp 910.
DOI: 10.12691/bb122
Received September 10, 2013; Revised November 02, 2013; Accepted November 05, 2013
Copyright © 2014 Science and Education Publishing. All Rights Reserved.
1. Introduction
Scientific communications following a research work leads to publications. Results of a research can be published in journals/books. Initially such scientific literature was available only in few journals and most was in printed format. Now with the advancement in information technology, there has been an upsurge in the number of publishers and many publications are available online. In the world of open access publication, it now becomes imperative that we should have a method to assess the effect of a scientific communication and measure of the researchers impact. From the time when a person’s research impact was considered as directly proportional to the impact factor of a journal in which his research is published, we now use many other indices including the hindex ^{[1, 2]}. Considering the fact that quality measure of a researcher is more significant than the quantity of output, assessment of a researcher/scientist’s is calculated taking in to consideration, the number of citation as a measure of impact. Of the available scientometrics, the Hirsh’s hindex is now widely used ^{[3]}.
2. A Review of HIndex
A person’s hindex is calculated as a figure that emerges after counting the number of papers cited among the ones that are published by a researcher to the minimum number of times it is cited in a set number of papers. For examples if a scientist publishes 50 papers, among them 40 are cited, and the ones that are cited, each paper is cited not less than 10 times, then his hindex equals to 10. The drawback of such calculation is that though you may have many papers that are hugely cited, it considers only those papers that are cited to a minimum number as your hindex and for your hindex to improve citations of your other papers should increase. Another issue with hindex was that, it takes a lot of time for a researcher’s hindex to raise even a single number. It does not consider the years of work of researchers and those who are active or inactive. It also ignores your highly cited papers. Modifications of hindex have emerged to the benefit of some researchers that consider scientists heavily cited publications and are called as gindex, m quotient, aindex and arindex ^{[4]}. Other modifications of hindex include hcindex and hrate. hcindex was designed to benefit current researcher’s and active scientists. hrate was considered as a modification to consider scientists who work for a short period resulting in high impact. Studies have evaluated the usage of hindex and have found it correlating well with the quality of publications ^{[5, 6]}. A previous study has clearly shown how two scientists (one with heavily cited papers and the other with papers cited only fewer times) with same number of publications have similar hindex. This shows the disadvantage of hindex in not considering your highly cited papers, neither taking in to account the total number of citations ^{[7]}.
I propose a newer and simpler means to calculate the impact of a researcher; this is called as Ramana’s researcher index (rindex). This method uses researchers total number of total number of citations and total number of papers published with the number of years in research.
The number of years in research is calculated as: First ≤5 years=1; 610 years=2; 1115 years=3; 1620 years=4; 2125 years=5 and so on
2.1. Author CreditsSecond author, third, fourth, fifth author and so on except last author in each paper results in an addition of 0.2 points, 0.3, 0.4, and 0.5 to the number of publications. The last author in many publications is considered as the senior most as well as the corresponding author will add only 0.1 points to the publications.
The advantage of this type of assessment is that it takes in to account all your publications, uses all the citations, the lowest to the highest (total citations) and the number of years in research where scientists with more number of research years and more citations have a chance to score more. This method also tries to solve the problem of authorship.
2.2. ExamplesCase I: A scientist with 25 publications and 50 total citations in 5 years will have an rindex of 2, whereas the scientist with fewer publications (15) and more citations (50) to his credit with same years (5years) of research has a more rindex (3.3).
Case II: we include scientists with 10 research years and consider one has 45 publications and 150 total citations resulting in rindex of 6.6, and the other has comparatively less publications (35) and more citations (150) giving him a high rindex of 8.4.
Case III: rindex of a researcher with 15 years of work is 7.8 including 75 publications and 200 citations to his credit. Another scientist with same years of research work having 60 papers and 200 total citations will have an r index of 9.9.
Case IV: A researcher with 20 years work has to his credit 100 publications and 300 total citations, amongst them he is first author for 40 of them, 2^{nd} author for 25 papers and third author for 15 papers and last author for 20 papers. Total number of publications is calculated as below.
Total publication points are
2.3. My rIndexPublications (35), Citations (59), 2^{nd} author in 2 and last author in 1 paper, 11y (3) of research
As evidenced by the above case examples, the number of citations and years of research influence the scientific impact of a scientist as calculated by Ramana’s researchers’ index (rindex).
A scientist with an rindex of >5 after 10 years, >15 after 20 years should be considered as a successful researcher.
3. Conclusion
Researcher impact is considered as directly proportional to the citation index i.e. the number of times a scientist’s research work has been cited. It has been noted that citation index and impact factor do not correlate well with the quality of a researcher and that it does not take in to consideration the contribution of authors ^{[8, 9]}. A recent paper has highlighted the bibliographic databases that have to be screened for calculation of citations of a researcher, that includes google scholar, JSTOR, academic search premier, scopus, psycINFO, enginefactor score pubmed and the web of knowledge ^{[10]}. Considering the fact that there are only fewer such methods to assess the quality of researchers worldwide, I believe that this method needs extensive evaluation by experts in the related fields. Advantage of rindex is that it does address the multiple author publications as tried by another study in the past ^{[11, 12]}. Future such evaluation of a researcher index needs to take in to account the scientific credit of a particular author in a given publications to make this assessment even more meaningful.
References
[1]  Garfield, E. Citation analysis as a tool in journal evaluation. Science 1972; 178: 471479. 
 In article  CrossRef 

[2]  Hirsch JE. An index to quantify an individuals’ scientific output. PNAS 2005; 102(46): 16591672. 
 In article  CrossRef PubMed 

[3]  Sidiropoulos, A., Katsaros, D. and Manolopoulos, Y. (2006). Generalized hindex for disclosing latent facts in citation networks, arXiv:cs.DL/0607066 v1. 
 In article  

[4]  Egghe, L. Theory and practice of the g index. Scientometrics 2006; 69: 131152. 
 In article  CrossRef 

[5]  Burrell, Q. Hirsch index or Hirsch rate? Some thoughts arising from Liang's data. Scientometrics 2007; 73: 1928. 
 In article  CrossRef 

[6]  ChunTing Zhang. A proposal for calculating weighted citations based on author rank. EMBO reports 2009; 10(9): 416417. 
 In article  CrossRef PubMed 

[7]  Bornmann L, Daniel HD, The state of h index research. EMBO Rep 2009; 10: 26. 
 In article  CrossRef PubMed 

[8]  Joseph Loscalzo. Can scientific quality be quantified? Circulation 2011; 123: 947950. 
 In article  CrossRef PubMed 

[9]  J A Sahel. Quality versus quantity: assessing individual research performance Sci Transl Med 2011; 84cm, 13. 
 In article  

[10]  Robin Kear and Danielle ColbertLewis. Citation searching and bibliometric measures resources for ranking and tracking. C&RL News 2011, 470474. 
 In article  

[11]  Hagen NT. Credit for coauthors. Science 2009; 323: 583. 
 In article  CrossRef PubMed 

[12]  van Raan, A. Comparison of the hirschindex with standard bibliometric indicators and with peer judgement for 147 chemistry research groups. Scientometrics 2005; 67: 491502. 
 In article  
