|Search:||Browse by Category:|
|How to choose the right preference function?|
There are six different shapes of preference function in the original PROMETHEE methods and in the PROMETHEE software. Here are some guidelines in choosing the right preference function for your criterion.
The V-shape (type III) and linear (type V) preference functions are best suited for quantitative criteria (e.g. prices, costs, power, ...). The choice will depend on whether you want to introduce an indifference threshold or not. Actually, V-shape is a special case of the linear one.
The Gaussian (type VI) preference function is less often used as it is more difficult to parameter (the s threshold value is somewhere between the q indifference threshold and the p preference threshold).
The Usual (type I) and Level (type IV) preference functions are best suited for qualitative criteria. In case of a small number of levels on the criteria scale (e.g. yes/no criteria or up to 5-point scale) and if the different levels are considered quite different from each other, the Usual preference function is the good choice. If you want to differentiate smaller deviations from larger ones, the Level preference function is more adequate.
The U-shape (type II) preference function is a special case of the Level one and is less often used.
These elements are implemented in the Visual PROMETHEE software Preference Function Assistant to help users to make the right choice.
Last update: 03:15 AM Sunday, March 25, 2012
© Bertrand Mareschal, 2011-2013. All rights reserved.