New GAIA Visualization Methods

In this paper, we consider multicriteria decision aid (MCDA) problems. GAIA is a descriptive extension of the PROMETHEE methods. It provides the decision maker with a two dimensional graphical representation of the multicriteria problem. A limit of the GAIA method is the loss of information resulting from the underlying principal components analysis that can result in inconsistencies with the PROMETHEE rankings. The aim of this paper is to address this limit by introducing new complementary GAIA-type visual representations. At first we introduce the context and briefly recall the principles of the PROMETHEE methods. We then introduce the GAIA method and propose two new extensions: GAIA-Stick gives a better view of the PROMETHEE ranking, while GAIA-Criterion enables the decision maker to focus on one specific criterion. Finally, a numerical example is used to illustrate the completed GAIA approach and to show how it can improve the decision process.