1. - 1 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Yaşar Tonta, Yurdagül Ünal & Umut Al Department of Information Management Hacettepe University Ankara, Turkey {tonta, yurdagul, umutal}@hacettepe.edu.tr The Research Impact of Open Access Journal Articles

2. - 2 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Outline  Some definitions  Open Access  Research impact  The nature of scientific disciplines  Methodology  Findings  Conclusion

3. - 3 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Related Terms Open Access: “Free …[online, full-text] access” to scientific publications Research impact: Number of times that each article is cited in literature Hard/soft; urban/rural; convergent/divergent scientific disciplines

4. - 4 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria The Nature of Scientific Disciplines Hard Urban Convergent Soft Rural Divergent PhysicsAnthropologyBiology

5. - 5 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Research Questions  Does the research impact of OA articles differ across the fields in sciences, social sciences, and arts and humanities?  If it does, do OA articles in hard, urban and convergent fields receive more citations (hence higher research impact) than those in soft, rural, and divergent ones?

6. - 6 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria  DOAJ journals  Journal selection criteria  Nine disciplines  Sample Methodology

7. - 7 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria The Nature of Scientific Disciplines Physics Mathematics Chem. Eng. Psychology Sociology Anthropology Economics Env. Sci. Biology hard, urban, convergentsoft, rural, divergent

8. - 8 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Sample Subjects # of journals in the sample# of total articlessample rate Physics 62,5431.2 Mathematics 161,0922.7 Chemical Engineering 38183.7 Economics 211326.5 Environmental Sciences 324712.1 Biology 76904.3 Psychology 427111.1 Sociology 39730.9 Anthropology 211127.0

9. - 9 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Scopus

10. - 10 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Descriptive Statistics  270 articles were cited 761 times  Articles with zero citations = 95 (35%)  Average number of citations  Biology6.4  Economics 5.1  Psychology0.9  Sociology0.8

11. - 11 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Distribution of Citations by Subjects N=761 hard, urban, convergentsoft, rural, divergent

12. - 12 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Self-citation Rates hard, urban, convergentsoft, rural, divergent

13. - 13 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Obsolescence for OA Articles

14. - 14 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Half-life for OA Articles  2 years  Physics  Mathematics  Biology  Psychology  3 years  Chemical Engineering  Economics  Environmental Sciences  Sociology  Anthropology

15. - 15 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Conclusion  Citation characteristics vary among disciplines  Citation behavior differs from self-archiving behavior  OA articles in hard, urban and convergent fields do not necessarily have higher research impact  OA articles in Biology, Economics and Anthropology received more citations

16. - 16 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Further Research  A more representative study with a larger sample size needs to be carried out  The relationship between research impact and self-archiving behavior should be investigated

17. - 17 ELPUB 2007, the 11th International Conference on Electronic Publishing, 13-15 June 2007, Vienna, Austria Yaşar Tonta, Yurdagül Ünal & Umut Al Department of Information Management Hacettepe University Ankara, Turkey {tonta, yurdagul, umutal}@hacettepe.edu.tr The Research Impact of Open Access Journal Articles