Multimedia database interfaces should be designed to be very user-adaptive, since there is no generally applicable model of user's search behavior or of his search intention. First, the challenging task for the interface is to present the most representative objects in an appealing and concise manner. Second, the interface has to identify the user's search intention from very few positive feedbacks. In particular for the latter there exist a lot of Relevance Feedback imple-mentations.
While most of them are considered as more or less heuristically proved parameter adjustment procedures, we treat Relevance Feedback as direct probability density estimation. Our density is defined as the