Sentence topics in Italian: An analysis on the CHROME Corpus1

The present study deals with the phonetic description of sentence topics in Italian tourist guides' speech. Topical coherence characterizes the communicative strategies that human experts adopt when delivering contents to the visitors of cultural sites. Topical progression, which ensures temporal, spatial, and referential conti-nuity, is frequently expressed by sentence topics as well. The relevant literature generally supports the idea of a topic accent and a rising-falling (or "hat") contour is de-scribed as the most frequent for the unmarked topic in Italian utterance structures, but other realizations are also possible. The hypothesis that we want to test in this work is whether this variability is due to specific factors. Hence, we investigate phonetic realization of sentence topics as a function of syntactic features-structure, function and weight-and textual-pragmatic features-discourse role considering & PLUSMN;aboutness, & PLUSMN;contrastiveness, & PLUSMN;givenness-. Spe-cifically, tonal events, i.e., accents and boundaries, phonetic phrasing, and disfluency phenomena were investigated. Results show that both syntactic and pragmatic factors play a role in the phonetic realization of topics, though they act at different levels. In particular, disfluencies are found to be affected by syntactic weight and givenness, while tonal events seem to depend mainly on the discourse role.