[2] It arises from the observation that different decision-making methods, both normative and descriptive, yield different results, when fed with exactly the same decision problem and data.
[3][4][5][6][7][8][better source needed] In a study reported in International Journal of Decision Support Systems[1] and Multi-Criteria Decision Making: A Comparative Study,[2] the following investigation was undertaken.
The methods used in that study were the weighted sum model (WSM), the weighted product model (WPM), and two variants of the analytic hierarchy process (AHP).
The first criterion was based on the premise that a method which claims to be accurate in multi-dimensional problems (for which different units of measurement are used to describe the alternatives), should also be accurate in single-dimensional problems.
[1][2] Other methods that have not been tested yet but may exhibit the same phenomenon include the following: A key role in this quest is played by the study of rank reversals in decision making.