Analysis conducted by the National Research Council's Office of Scientific and Engineering Personnel for this study. Analysis conducted by Me National Research Council's Office of Scientific and Engineering Personnel for this study. NSF 1996c, p. 34. NSF 1996c, p. 8. Other problems occur because journal prestige and variation among disciplines is not considered.
Time lag is a problem.
There can be differential counting or miscounting due to multiple authorship, multiple field allocation, limits on the number of citations by journal, and changes in the number of journals in the field over time. And authors might use the same material with slight elaborations or break up a major article into several minor ones. Thus, citation rates measure visibility but not inaccessible work and not necessarily quality. Figure B- 16 compares the number of papers produced by US mathematicians with those produced in the European Community. Another measure that was used in the UK report is the relative citation impact.