Headless in Berlin: Headless (nominal) structures in Head-Driven Phrase Structure Grammar

This paper deals with the status of heads in Head-Driven Phrase Structure
Grammar (HPSG). Firstly, background assumptions are presented: the lexical
representation of valence at the head and projection of head features. Secondly, I discuss
criteria for determining the head of a phrase. I use nominal structures as an
example, since the DP/NP debate is still undecided across frameworks, and exploring
the arguments from an HPSG perspective may be interesting for readers. Zwicky’s
(1985) criteria are discussed, and I show that most of them do not decide the
issue for German nominal structures, but assignment of semantic roles by relational
nouns and selectional relations in idioms (Osborne & Groß 2012, Bruening 2020)
support NP structures. I discuss nominal structures with non-overt nouns and
copulaless sentences in African American Vernacular English (AAVE) and argue
for an empty nominal head. I show that empty elements can be eliminated from
grammars but argue that they are nevertheless useful in nominal structures and
copula constructions in AAVE, since they capture generalizations. However, there
are other structures like Jackendoff’s (2008) N-P-N construction that should be an-
alyzed as unheaded. The paper closes with general considerations about the use
of empty elements in grammars, arguing that they should be detectable in the
input by systematic variation with overt material. This excludes the assumption of
empty elements like AgrO or Topic in grammars of languages like German, since
there is no overt material associated with these heads.