Open AccessDealing with optional complements in HPSG-based grammar implementations
Author(s) -
Kordula De Kuthy,
Detmar Meurers
Publication year - 2003
Publication title -
proceedings of the international conference on head-driven phrase structure grammar
Language(s) - English
Resource type - Journals
ISSN - 1535-1793
DOI - 10.21248/hpsg.2003.5
Subject(s) - computer science , head driven phrase structure grammar , phrase structure grammar , grammar , rule based machine translation , natural language processing , generality , complement (music) , feature (linguistics) , realization (probability) , artificial intelligence , programming language , linguistics , context free grammar , mathematics , generative grammar , psychology , philosophy , biochemistry , chemistry , statistics , complementation , psychotherapist , gene , phenotype
This paper discusses how the English Resource Grammar (ERG)captures the optionality of certain complements of verbs based ona single lexical entry coupled with an ontology of markingsdistinguishing optional from obligatory as well as unrealized fromrealized elements. Subject-head and head-complement structuresare modified accordingly, but due to the lack of a possibility toexpress and use relational goals in grammars implemented in theLKB system, the ERG encoding falls short of the goal of treatingoptional complements in a general way. Instead, it requires twonew types of ˋauxiliary' phrases which are otherwise unmotivated.We show that the problem can be overcome by using a recursiverelation selecting a member from a list. The use of a leanimplementation platform not supporting such relational goals, suchas the LKB, thus results in a loss of generality of the grammarsthat can be expressed, which undermines the closeness of theimplemented grammar to current linguistic analyses as one of thehallmarks of HPSG-based grammar implementation. The case studypresented in this paper thus supports the position argued in Götzand Meurers (1997) that a system for the implementation ofHPSG-based grammars should include both universal implicationalprinciples as well as definite clauses over feature terms.