The Pairwise Comparisons frame displays one comparison at the time. When one comparison is completed, a new one is produced. The algorithm consists of two phases:
1 In the first phase, comparisons are selected so that all elements are connected. If more than one comparison connects unconnected elements, one of the comparisons is selected randomly. As a consequence, when the same view is compared for two criteria, it is likely that different comparisons are displayed.
For example, if a view contains 10 elements, nine comparisons are needed to connect the elements. When the nine comparisons are completed, priorities can be calculated.
2 In the second phase, the algorithm searches for the comparison that contributes the most information. The algorithm follows these rules:
▪ Finds at least two elements that are part of as few comparisons as possible.
▪ If only two elements are found, those elements are compared.
▪ If more than two elements are found (for example, five elements are part of two comparisons each), the two elements with the highest priorities are compared.
Note The algorithm works differently when it has to compensate for picked elements.