UMR 8118, CNRS, Université Paris Descartes, Paris, France, Departments of Statistics and Neurobiology, University of Chicago, Chicago, Illinois, United States of America.|Departments of Statistics and Computer Science, University of Chicago, Chicago, Illinois, United States of America.|UMR 8118, CNRS, Université Paris Descartes, Paris, France, Departments of Statistics and Neurobiology, University of Chicago, Chicago, Illinois, United States of America.