Free Download — Description: Data describes a collaboration network of scientists posting preprints on the condensed matter archive at www.arxiv.org. This version is based on preprints posted to the archive between January 1, 1995 and March 31, 2005. The network is weighted, with weights assigned as described in M. E. J. Newman, Phys. Rev. E 64, 016132 (2001). These data can be cited ...