Towards a discourse-based model of English sentence intonation

Sammanfattning: English non-expressive, declarative sentence intonation is examined in a discourse context. A rule system, geared to a text-to-speech context is developed which assigns sentence prominences related to information focus. The realization of these prominences with respect to the phonetic parameter of pitch (F0) is also described with a pitch generating algorithm. The dynamics of information focus in English is shown to be accountable for by a hierarchy of grammatical functions interacting with a contextual notion of coreference. Projection of focal prominence is effected by a subroutine which assigns prominence either to the head or to the modifier of the constituent realizing a particular grammatical function, depending on the coreferential status of the associated lexical items. The model assumes three degrees of prominence associated with the three grammatical functions (Subject, Predicate, Predicate complement). These are realized by varying heights of F0 peaks described in relation to the baseline of a phonological 'grid' characterizing the speaker's F0 range and declination constants. A fourth degree of prominence is also shown to be required on prefocal lexical heads. The notion of contrastive prominence conditioned by syntactic parallelism and identity relations is examined and preliminary rules are formulated for assigning and synthesizing the associated F0 contours. The problem of noncontraction of the copula is also related to the issue of contrastive prominence. The status of the notion of 'phonological phrase' is examined in the light of a grammar which includes a focus assigning component and a number of phonological processes (e.g. 'rhythm rule') are reanalyzed.