TY - JOUR AV - none N2 - For many complex networks present in nature only a single instance, usually of large size, is available. Any measurement made on this single instance cannot be repeated on different realizations. In order to detect significant patterns in a real-world network it is therefore crucial to compare the measured results with a null model counterpart. Here we focus on dense and weighted networks, proposing a suitable null model and studying the behaviour of the degree correlations as measured by the rich-club coefficient. Our method solves an existing problem with the randomization of dense unweighted graphs, and at the same time represents a generalization of the rich-club coefficient to weighted networks which is complementary to other recently proposed ones. TI - On the rich-club effect in dense and weighted networks A1 - Zlatic, Vinko A1 - Bianconi, Ginestra A1 - Díaz-Guilera, Albert A1 - Garlaschelli, Diego A1 - Rao, Francesco A1 - Caldarelli, Guido SN - 1434-6028 Y1 - 2009/// ID - eprints1091 SP - 271 IS - 3 EP - 275 JF - The European Physical Journal B UR - http://dx.doi.org/10.1140/epjb/e2009-00007-9 KW - PACS: 89.75.Hc Networks and genealogical trees; 89.75.Fb Structures and organization in complex systems VL - 67 ER -