This project will study collective decision making in groups of interacting animal and/or human. Specifically, it will include analyzing real experimental data in social mice and/or in pedestrian dynamics, using a combination of agent based model and statistical inference to build interaction models that explains the observed collective behavior, analyzing the information flow between individuals of the group using techniques from causality analysis and information theory, and designing plausible probes to be implemented by experimental collaborators to perturb and control the collective behavior. It may also include investigating toy models to study the impact of perturbation on collective decision making. The candidate is expected to have experience of coding, solid background in statistical physics, and motivation to work closely with data. This internship will be supervised by Xiaowen Chen, CNRS researcher at LPENS.