Two-dimensional graphic representation and analysis of learners’ traces

The learner follow-up in problem solving is a hard issue. It is more difficult when there are a lot of learners or when those learners use distance learning. We propose in this paper a two-dimensional graphic representation of student's traces. To achieve this goal, we use and modify numerical analysis algorithms (automatic dimensionality reduction algorithms like Self Organizing Map and Stochastic Neighbour Embedding). We also propose a new distance between sets whose elements have semantic similarity. Finally, we validate and improve our algorithm with simulated data and experimental data