Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
The well-known swap distance (Kemeny, 1959; Kendall, 1938 and Hamming, 1950) is analyzed. On weak preferences, this function was characterized by Kemeny (1959) with five conditions; metric, betweenness, neutrality, reducibility, and normalization. We show that the same result can be achieved without the reducibility condition, which shows the Kemeny distance is much less demanding than it seems. We provide a new and logically independent characterization of the Kemeny distance and provide some insight to further analyze distance functions on preferences.