Number of downloaded articles

(1)

Yaşar Tonta & Yurdagül Ünal

Department of Information Management Hacettepe University

{tonta, yurdagul}@hacettepe.edu.tr yunus.hacettepe.edu.tr/~tonta/tonta.html

Consortial Use of Electronic

Journals in Turkish Universities

(2)

Plan

• Use of electronic journals

• Consortium development in Turkey

• Consortial use of ScienceDirect (SD) journals

• Conclusions

(3)

Research Setting and Method

• 115 Turkish universities, 2.5M students, 80K faculty

• The Consortium of Anatolian University Libraries (ANKOS) (www.ankos.gen.tr )

• The Turkish Academic Network and Information Center (ULAKBİM) (www.ulakbim.gov.tr )

• The National Academic License of Electronic Resources (EKUAL)

• Elsevier’s ScienceDirect journals

• Analysis of more than 25M articles downloaded

from ScienceDirect journals (2001-2007)

(4)

Research Questions

• Core journal titles based on downloaded articles

• Distribution of downloaded articles and power laws (Bradford, Pareto, and Price)

• Stability of core journal titles

• Relationship between use based on downloads and impact factors / total number of citations

• The Urquhart Law (not reported in the

paper)

(5)

Findings

(6)

Number of full-text articles downloaded from ScienceDirect journals (2001-2007)

5,843,049 (est.) 5,652,780

5,264,423 4,575,094

1,362,934 810,203

3,346,381

0 1.000.000 2.000.000 3.000.000 4.000.000 5.000.000 6.000.000 7.000.000

2001 2002 2003 2004 2005 2006 2007

Year

N u m b er o f d o w n lo a d ed a rt icl es

(7)

Bradford curves for use of ScienceDirect journals

0 10 20 30 40 50 60 70 80 90 100

0 150 300 450 600 750 900 1050 1200 1350 1500 1650 1800 1950 2100 2250

Cumulative number of journals

C u m u la tiv e p er ce n ta g e o f d o w n lo ad ed a rtic le s ( % )

2001/07 2001 2002 2003 2004 2005 2006 2007

Number of journals

Region 2001/07 2001 2002 2003 2004 2005 2006 2007

1 105 77 83 95 103 103 92 93

2 273 206 225 255 271 274 262 257

3 1719 950 1292 1304 1409 1498 1553 1663

Total 2097 1233 1600 1654 1783 1875 1907 2013

(8)

Yearly distributions of journal titles by region

1 10 100

2001-2007 2001 2002 2003 2004 2005 2006 2007

P er cent age of jour nals ( % )

1st region 2nd region 3rd region

(9)

Correlation coefficients for common core journal titles

Years

Spearman rank order correlation coefficient (ρ)

2001-2002 0.402

2002-2003 0.706

2003-2004 0.778

2004-2005 0.780

2005-2006 0.791

2006-2007 0.874

(10)

Common core journals

Ranks by years

Journal name 2001/07 2001 2002 2003 2004 2005 2006 2007

Food Chemistry 1 9 9 12 1 1 2 1

European Journal of Operational Research 2 5 5 4 2 2 3 2

Lancet, The 3 29 11 1 3 3 5 6

Journal of Materials Processing Technology 4 6 2 2 4 6 7 3 Journal of Food Engineering 5 26 24 21 6 8 4 5 Tetrahedron Letters 6 19 13 15 12 4 10 15 Journal of Chromatography A 7 13 10 11 10 11 9 14 Analytica Chimica Acta 10 7 12 6 18 17 12 13

Water Research 11 3 4 10 15 16 22 30

Cement and Concrete Research 12 27 6 5 19 5 30 52 Materials Science and Engineering A 13 15 23 19 16 20 17 8

Tetrahedron 15 32 27 23 25 7 14 17

Polymer 16 18 22 16 23 19 15 11

Biomaterials 17 49 19 20 14 15 20 26

Surface and Coatings Technology 18 24 16 36 26 18 18 10

(11)

The most frequently used top 10 SD journals

World-wide Turkey (2001-2007)

Journal name Rank % Rank % The Lancet 1 1.56 3 0.71 Tetrahedron Letters 2 1.55 6 0.55

Cell 3 0.99 919 0.03

Biochemical and Biophysical Research Communications

4 0.97 47 0.27

Tetrahedron 5 0.93 15 0.47

FEBS Letters 6 0.87 96 0.21

Journal of Chromatography A 7 0.67 7 0.54

Journal of Molecular Biology 8 0.60 309 0.09

Journal of the American College of Cardiology 9 0.58 8 0.54

Brain Research 10 0.55 30 0.36

(12)

Download data and power laws

• Did not fit the Bradford Law

– About 5%-6% of all journal titles (instead of less than

0.1%) satisfied one third of all download requests

• Did not fit the Pareto Law (80/20 Rule)

– 29% of journals (instead of 20%) satisfied 80% of all requests

• Did not fit the Price Law

– Half the download data came

Pareto

Price

Bradford

Percentage of downloaded ar ticles (%)

(13)

Correlation between use and impact factors / total number of citations

N Ranks

Use - impact factor r = 0.318 ρ = 0.113

Use - total number of citations r = 0.368 ρ = 0.253

(14)

The Urquhart Law

• The interlibrary use reflects intralibrary use.

• Correlation between ULAKBİM’s

ScienceDirect OnSite use and universities’

use of ScienceDirect journals:

– Spearman’s ρ = 0,833, N = 1702

• Correlation between ULAKBİM’s and

universities’ use of ScienceDirect journals:

– Spearman’s ρ = 0,489, N = 1384

(15)

Conclusions

Few core journals satisfying majority of the download use

Core journals are common

No meaningful relationships exist between use based on download data and that on impact factors / total citations

Current journals used more often

The Urquhart Law is also valid for electronic journals: Journals used more often at