The importance of the evaluation for universities is fully recognized. Measuring students' satisfaction with their higher education institutions is not new. In several countries, some of those data are even mandatory and transversal to institutions for the accreditation of their courses. They contribute then as indicators to compare and validate their classifications. However, this validity is, for some time, challenged. In this study, we focus on the influence of the advocacy roles of the students on schools’ evaluations. As a starting hypothesis, we supposed that depending on the intent to promote his school, the perceived quality should differ significantly.