Heterogeneity, quality, and reputation in an adaptive recommendation model G. Cimini, M. Medo, T. Zhou, D. Wei and Y.-C. Zhang Eur. Phys. J. B, 80 2 (2011) 201-208 Published online: 06 January 2011 DOI: 10.1140/epjb/e2010-10716-5