Given a headword and a context window, a statistical approach identifies the word combinations from the context inclusive of the head word with significant lexical statistics as the collocations; a syntactic approach resorts to syntactic knowledge acquired from a parser to refine the candidates, assuming that collocation words are syntactically dependent; a semantic approach exploits semantic relations such as synonyms obtained from WordNet to overcome the inaccuracies caused by insufficient statistics; a categorical approach adopts a set of carefully tailored rules to identify collocations of different types, which may potentially achieve better results, but the method turns out to be less generalizable.
the general statistical methods based on co-occurrence statistics are depicted, followed by the techniques for identifying specific types of proper nouns based on their particular formation patterns.