Towards the Automatic Learning of Idiomatic Prepositional Phrases

The objective of this work is to automatically determine, in an unsupervised manner, Spanish prepositional phrases of the type preposition nominal phrase preposition (P−NP−P) that behave in a sentence as a lexical unit and their semantic and syntactic properties cannot be deduced from the corresponding properties of each simple form, e.g., por medio de (by means of), a fin de (in order to), con respecto a (with respect to). We show that idiomatic P−NP−P combinations have some statistical properties distinct from those of usual idiomatic collocations. We also explore a way to differentiate P−NP−P combinations that could perform either as a regular prepositional phrase or as idiomatic prepositional phrase.