The fifth “One World webinar” organized by YoungStatS will take place on September 15th, 2021. Selected young European researchers active in the areas of probability and machine learning will present their recent contributions. The webinar is joint cooperation between the Young Researchers Committee of the Bernoulli Society for Mathematical Statistics and Probability and the YoungStatS project. Speakers: Antoine Marchina (Université de Paris) and Geoffrey Chinot (ETH Zurich) Discussant: Prof. Gábor Lugosi, ICREA Research Professor at Pompeu Fabra University and Barcelona GSE Research Professor, and Blackwell Lecture speaker at the Bernoulli-IMS 2021 World Congress in Probability and Statistics