A commonality in many of these approaches is that they model the problem of entity coreference as a collection of decisions between mention pairs (Bagga and Baldwin, 1999;Soon et al., 2001;McCallum and Wellner, 2004;Singla and Domingos, 2005;Bengston and Roth, 2008).
coreference is solved by answering a quadratic number of questions of the form "does mention A refer to the same entity as mention B?"