It provides a ranking-based nonmonetary measure of human resource value. While employees can simply be ranked by selecting the highest (and the next highest, and so on) based on a particular dimension, the alternation ranking method is a modification that helps simplify the process of judgment, thereby increasing its reliability.
The method consists of first selecting an employee with the highest value and then the person with the lowest value. Subsequently, the person with the highest value (among the remaining people) is selected, as also the one therein with the lowest value. Iterations continue until all employees have been ranked.
A related approach is the paired comparisons method which obtains rankings by a series of comparisons between pairs of individuals. Both these methods have proved more reliable than the simple ranking method.