Controversies arising from which similarity measures can be used in co-citation analysis

Pearsonʹs r has been used as similarity measure in author co-citation analysis since the introduction of this technique in the 1980s. However, some scientists supported that Pearsonʹs r coefficient does not fulfill mathematical conditions of a good similarity measure, and therefore should not be used in co-citation analysis. They proposed alternatives measures that yield much precisions. Other scientists defend the use of Pearsonʹs coefficient and supported that it does well the job author cocitation analysis isfor. This article makes the point of the controversy that rose several years ago and fed in the Journal of the American Society of Information Science and Technology (JASIST) about what similarity measure to use in author co-citation analysis and similar techniques.