Analysis of the Obsolescence of Citations and Access in Electronic Journals at University Libraries

This study analyzes the correlation between the obsolescence of citations and access concerning a broad range of subjects, including fields that have not been dealt with in previous studies, shedding light on the differences between these two types of obsolescence and the characteristics for each field. The analysis investigates approximately 1,200 journals that were randomly sampled from 11 subject fields in SpringerLink and 20 subject fields in ScienceDirect. Metrics such as cited half-life and download half-life are employed to examine the relationship between the rate of obsolescence of citations and access. As a result, no strong correlation between citations and access is observed in most fields with regard to the short-term obsolescence. As for the long-term obsolescence, on the other hand, comparatively strong and significant correlations are seen in natural sciences other than medicine-related fields (p < 0.05).