This work focuses on graph algorithmics.A first approach consists of modeling the interaction structures of systems as graphs, and questioning these models.More specifically, we are exploring the various techniques for observing graphs resulting from human activity, user mobility or the evolution of structures connecting computer systems, and questioning their ability to provide a faithful representation of the real system under consideration.

The second approach reverses the previous one, by studying graphs as the product of unknown algorithms.The aim of the research is to understand the (unknown) algorithms that generated these graphs. This approach is fundamental to algorithmic transparency, for example, in order to understand the mechanisms of recommendation engines by observing only the inputs and outputs of these systems[1].

[1] Le Merrer E., Tredan G., The Topological Face of Recommendation, 6th  International Conference on Complex Networks and their Applications (COMPLEX NETWORKS 2017), pp.897-908, 2017.