Demographic Research a free, expedited, online journal of peer-reviewed research and commentary in the population sciences published by the Max Planck Institute for Demographic Research Konrad-Zuse Str. 1, D-18057 Rostock · GERMANY www.demographic-research.org DEMOGRAPHIC RESEARCH VOLUME 20, ARTICLE 22, PAGES 541-558 PUBLISHED 20 MAY 2009 http://www.demographic-research.org/Volumes/Vol20/22/ DOI: 10.4054/DemRes.2009.20.22 Research Article Keeping a learned society young Herbert Dawid Gustav Feichtinger Joshua R. Goldstein Vladimir M. Veliov c  2009 Herbert Dawid et al. This open-access work is published under the terms of the Creative Commons Attribution NonCommercial License 2.0 Germany, which permits use, reproduction & distribution in any medium for non-commercial purposes, provided the original author(s) and source are given credit. See http://creativecommons.org/licenses/by-nc/2.0/de/