Page 104 - JOURNAL OF LIBRARY SCIENCE IN CHINA 2015 Vol. 41

Xincai WANG, Haining WANG / Empirical study on journal literature guarantee of academic library: A case study of Wuhan University 103

2.2 Unavailability study

There are two causes which may result in the unavailability of sample citations: the “title
unavailability” and the “issue unavailability”. “Title unavailability” means a certain journal
wasn’t included in any full-text databases of the Wuhan University Library. “Issue unavailability”
describes the other situation that: a certain journal was embedded in at least one full-text database
of the collection, but the publishing year of certain cited references fails to suit the temporal
coverage of this journal. By distinguishing the two causes, Table 2 shows the statistics of
unavailable cited references.

Table 2. Unavailable cited references, source journals, and ACF of available journals
Percentage of Percentage of
No. of No. of ACF of
Resource Cause cited unavailable source unavailable unavailable
sample
source
references journals journals
citations (%) journals (%)
Title unavailability 8 744 13.06 2 531 36.31 3.45
E Issue unavailability 7 598 11.35 964 13.83 7.88
Total unavailability 16 342 24.40 3 495 50.14 4.68

Title unavailability 31 919 47.66 4 746 68.09 6.73
P Issue unavailability 77 0.11 36 0.52 2.14
Total unavailability 31 996 47.78 4 782 68.61 6.69

Title unavailability 56 542 84.43 6 230 89.38 9.08
OA Issue unavailability 694 1.04 116 1.66 5.98
Total unavailability 57 236 85.47 6 346 91.05 9.02

Title unavailability 5 756 8.60 1 858 26.66 3.10
E∪P∪OA Issue unavailability 2 298 3.43 423 6.07 5.43
Total unavailability 8 054 12.03 2 281 32.73 3.53

Generally, access failure caused by unavailable titles is more serious than that caused by
unavailable issues. As for electronic collection, the title unavailability and issue unavailability lead
to a similar number of access failure, while the ACF of unavailable titles is below half that of the
unavailable issues.
Pinning the inflexible mode as package deal on electronic collection acquisition, two
probable causes of the unavailable issues are identified: 1) certain databases might have
defects in continuity. 2) Some cited references were not included in the temporal coverage