Mark de Vos from Rhodes Linguistics explored asymmetries in Specifier-Head word order in English at a Departmental Research Seminar held on Tuesday 16 August. He demonstrated that there is only mixed empirical evidence in English to back up the prediction of the Linear Correspondence Axiom (LCA) that specifiers universally precede their heads.
Mark argued in his presentation that there is an alternative to the LCA. He proposed that under some circumstances PF can locally invert the order of a specifier and its head in order to conform to linearization requirements.
Within the Principles and Parameters framework, the Head Parameter allowed, in principle, for either heads or specifiers to occur on the left or right. However, there appears to be an asymmetry between heads and specifiers: while heads can indeed occur on the left or right, it seems to be the case that "no clear case of a generally Specifier-final language has been
discovered" (Roberts 1997:26). Kayne (1994) also notes that even within single languages, head-complement orders are much more stable and harmonic than head-specifier orders.
In his presentation, Mark showed that it is not entirely clear that specifiers do, in fact, precede their heads in all situations and a heterogenous set of auxiliary assumptions are required to explain the word order facts (including null heads, obligatorily empty specifiers, unmotivated head movement etc). The aim of his presentation was, in Noam Chomsky's words, to "[push] a precise but inadequate formulation to an unacceptable conclusion" in the interests of opening up debate on these issues.