Average Percentile

The percentile of a publication is determined by creating a citation frequency distribution for all the publications in the same year, subject category and of the same document type (arranging the papers in descending order of citation count), and determining the percentage of papers at each level of citation, i.e., the percentage of papers cited more often than the paper of interest. If a paper has a percentile value of one, then 99 percent of the papers in the same subject category, year and of the same document type have a citation count that is lower.

Sample Calculation of Percentile for a Set of 11 Documents

Times Cited

Percentile

1,000

9.09

50

18.18

10

27.27

3

36.36

2

54.55

2

54.55

1

81.82

1

81.82

1

81.82

0

100.0

0

100.0

A percentile indicates how a paper has performed relative to others in its field, year and document type and is therefore a normalized indicator. For any set of papers, an Average Percentile can be calculated as the harmonic mean of all the percentiles of all the papers in the set. In the case that a paper is assigned to more than one category, the category in which the percentile value is closest to zero is used (i.e., the best performing value). Percentile values are rounded to the second decimal place.