Sjr

Vicente P. Guerrero Bote

SCIMAGO JOURNAL RANK

http://www.scimagojr.com/10/27/201

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Sections

1. ISI Impact Factor (Pros and Cons).

2. Previous Work.

3. PSJR (Description).

1. Three Compounds of PSJR.

2. PSJR Pros and Cons.

4. SJR (Description).

5. Conclusions.

6. Distributions.

7. Opinions.

8. How to use?

9. Future.

Appendix: http://www.scimagojr.com/

http://www.scimagoir.com/ 10/27/2010


1. ISI Impact Factor

Pro+: Takes into account the Citation Quantity. Simple Computation. Intuitive Interpretation. Popular.

Con-: Not normalized. Ignores Citation Quality:

Journal Prestige. Different referencing characteristics of different scientific

fields. Permit journal to influence by self citations. Disagreement with Experts’ Perceptions.

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Eigenvector Centrality, Bonacich (1972).Journal Influence, Pinski y Narin (1976).Google’s PageRank (1998).

2. Previous Work

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3. PSJR

PSJRi -Previous Scopus Journal Rank of the Journal i. Cji - Citation from journal j to journal i.Cj - Number of References of journal j.d - Constant, normally 0.9.e - Constant, normally 0.0999.N - Number of JournalsArtj - Number of Articles of journal j

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3.1 Three Compounds of PSJR

0,01%: 1/N Prestige for being considered.

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0,01%: 1/N Prestige for being considered.9,99%: Arti/Total Arts proportionate to the

number of articles.

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0,01%: 1/N Prestige for being considered.9,99%: Arti/Total Arts proportionate to the

number of articles.90%: Proportionate to the PSJR of the cites.

Scopus.3 year citation Window.Limiting Self-Referencing to 33%.

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3.2 PSJR Pros and Cons

Pro+: Takes into account the Citation Quantity. Takes into account the Citation Quality.

The quality of the citing journal with its own PSJR. The number of references of the citing journal dividing

by it. Good records for its use by Google. Fast computation. Random walk model reflects perception. PSJR Reflects the journal influence. PSJR normalized to 1.

Con-: Ignores the number of articles published by a journal.

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4. SJR

Arti – Number of articles published by the journal in the citation window.

Citation Window of 3 years.Scopus data.Limiting Self-Referencing to 33%.

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ii Art

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5. Conclusions

SJR reflects the Journal Quality (instead of the influence).

SJR enlarges the Citation Window.SJR agrees with the Experts’ perceptions in

recent studies.

Takes into account the Citation Quantity. Takes into account the Citation Quality.

The quality of the citing journal with its own PSJR. The number of references of the citing journal dividing by it.

Good records for its use by Google. Fast computation. Random walk model reflects perception.

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6. Examples

Rank Distributions.

Dispersion.

Top Rankings

Correlations.

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6.1 Rank Distribution

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6.2 Dispersion

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Title SJR Rank SJR Rank (3y)Annual Review of Immunology 18.477 1 2

Cell 14.117 2 7

Annual Review of Biochemistry 13.211 3 5

Annual Review of Cell and Developmental Biology 12.013 4 8

Nature Immunology 10.253 5 21

Nature reviews. Molecular cell biology 10.061 6 16

Nature Genetics 9.923 7 13

Immunity 9.284 8 27

Ca-A Cancer Journal for Clinicians 8.717 9 1

Annual Review of Genetics 8.545 10 23

6.3 SJR Top Rankings

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Title JIF(3y) Rank JIF(3y) Rank SJRCa-A Cancer Journal for Clinicians 60.935 1 9

Annual Review of Immunology 47.393 2 1

Physiological Reviews 35.120 3 16

Reviews of Modern Physics 34.351 4 46

Annual Review of Biochemistry 34.198 5 3

Annual Review of Neuroscience 33.492 6 11

Cell 30.827 7 2

Annual Review of Cell and Developmental Biology 27.558 8 4

New England Journal of Medicine 27.434 9 50

Briefings in bioinformatics 25.784 10 58

6.3 IF(3y) Top Rankings

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Spearman: 0.9331Pearson: 0.8036

Subject areas (27) Specific subject areas (295)

Spearman x = 0.9338 || sd = 0.0409 x = 0.9239 || sd = 0.0713

Pearson x = 0.8200 || sd = 0.1350 x = 0.8582 || sd = 0.1242

6.4 Correlations

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7. Some Opinions

“…another vote in favour of the basic idea of ranking journals using the sorts of Eigenvector centrality methods that Google’s PageRank uses.” Carl Bergstrom

“This means not all citations are considered equal; those coming from journals with higher SJRs are given more weight.” Nature News, 2008

“The top journals in SJR rankings by discipline are often broadly similar to those generated by impact factors, but there are also large differences in position.” Nature News, 2008

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7. Some Opinions

“… the SJR, albeit derived conceptually from the PageRank concept, seems to offer a good alternative to the Impact Factor. ” Loet Leydesdeorf, 2008

“…the SJR indicator attributes different weight to citations depending on the "prestige" of the citing journal…” Falagas et al., 2008

“Both employ complex algorithms to create relative measures and may seem opaque to the user and difficult to interpret,” Jim Pringle, 2008

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8. How To Apply?

PSJR in Libraries: Global Influence of a Scientific Journal.

SJR in Research Evaluation: Indicates the worth per paper. Observed impact correlates with the quartiles of the

journals.

Still by Scientific areas.

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9. Future: SJR2

Weight Citation: PSJR. Subject Proximity (Cocitation).

Dangling Distribution: Proportionally to PSJR.

Reference Normalization: Citation Window. Scopus.

Autoreferencing Limited.

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For more Reference

González-Pereira, B., Guerrero-Bote, V. P. y Moya-Anegón, F. (2010). A new approach to the metric of journals’ scientific prestige : The SJR indicator. Journal of Informetrics, 4(3), 379-391. DOI: 10.1016/j.joi.2010.03.002.

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Vicente P. Guerrero Bote 10/27/2010


Thank you for your time and your attention.

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