tailieunhanh - Báo cáo khoa học: "Unifying Parallels"

I show that the equational treatment of ellipsis proposed in (Dalrymple et al., 1991) can further be viewed as modeling the effect of parallelism on semantic interpretation. I illustrate this claim by showing that the account straightforwardly extends to a general treatment of sloppy identity on the one hand, and to deaccented foci on the other. I also briefly discuss the results obtained in a prototype implementation. | Unifying Parallels Claire Gar dent Computational Linguistics University of the Saarland Saarbriicken Germany Abstract I show that the equational treatment of ellipsis proposed in Dalrymple et al. 1991 can further be viewed as modeling the effect of parallelism on semantic interpretation. I illustrate this claim by showing that the account straightforwardly extends to a general treatment of sloppy identity on the one hand and to deaccented foci on the other. I also briefly discuss the results obtained in a prototype implementation. 1 Introduction Dalrymple et al. 1991 Shieber et al. 1996 henceforth DSP present a treatment of VP-ellipsis which can be sketched as follows. An elliptical construction involves two phrases usually clauses which are in some sense structurally parallel. Whereas the first clause we refer to it as the source is semantically complete the second or target clause is missing semantic material which can be recovered from the source. Formally the analysis consists of two components the representation of the overall discourse . source and target clauses and an equation which permits recovering the missing semantics. Representation s A R Ti Equation R Si . Sn s s is the semantic representation of the source Si . sn and Ti . Tn are the semantic representations of the parallel elements in the source and target respectively and R represents the relation to be recovered. The equation is solved using Higher-Order Unification HOU Given any solvable equation M N HOU yields a substitution of terms for free variables that makes M and N equal in the theory of a 7 -identity. The following example illustrates the workings of this analysis 1 Jon likes Sarah and Peter does too. In this case the semantic representation and the equation associated with the overall discourse are Representation like j s A R p Equation R j like j s For this equation HOU yields the substitution1 R x s and as a result the resolved semantics of the target