“…Such an assumption is becoming less and less sustainable in a world where non-expert users are involved in annotating a constant stream of data, be it the flow of news in the Web (see, e.g., [10]), or the flow of sensor data in pervasive and ubiquitous computing (see, e.g., [15,17]). In the case of the latter scenario, the same input can be proposed multiple times, resulting in it being often labeled differently even by the same user [18].The research presented here is part of, and motivated by, a long-term series of experiments (two experiments per year for two years) aimed at studying the University student life and at correlating the students' behaviors with their academic performance, measured concerning grades and credits passed. The long-term goal is to support students who should increase their performance, thus also minimizing the possibility of a failure in getting the degree.…”