title: How to lift a model for individual behaviour to the population level?
authors.affiliation: Mathematical Institute and Institute of Biology, Leiden University, PO Box 9512, 2300 RA Leiden, The Netherlands.
authors.forename: O
authors.initials: O
authors.lastname: Diekmann
authors.forename: J A J
authors.initials: JA
authors.lastname: Metz