When I compare citation activity for urban planning faculties (i.e., departments), I usually use the median of total faculty citations. Faculties are generally small and there tends to be an outlier among them. A question that arises is whether more experienced faculties have higher citation levels because they have a larger base of publications which had a longer time to accumulate citations. Of the 120 urban planning programs that I track in North America, the average years of program faculty service is about 19 years and the median number of citations is 593 (ln(593) = 6.38). The cluster of planning programs averaging between 13.5 and 24.5 years of service represents nearly 85% of all programs. As shown on the graph below, there is virtually no change in the trend line for these programs. In other words, age does not appear to be a significant factor. As would be expected the youngest faculties do in fact have fewer citations, but the oldest do not show a marked increase.
Note: The Ohio State University (shown with the red square symbol) is actually one of the younger faculties but has a faculty-wide citation level near the average for all programs.
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