The present study examines how global tempo adjustment can reflect the allocation of emphasis, whether emphasis is a local prosodic phenomenon, whether the degree of perceived emphasis corresponds systematically to speech signal, and whether temporal features can be derived from production analysis. Results from acoustic analysis showed positive correlations between perceived emphasis to both local and global tempo modulations; higher emphasis of higher degree corresponds to overall tempo slowing while duration adjustment of individual phones is independent of segmental make-up. To demonstrate how global tempo modulations by utterance from discourse information may affect local tempo adjustment of by words, we normalized all possible effects of discourse factors and found sharper contrasts between emphasis and non-emphasis. The present results suggest that (1) emphasis should not be treated as a local prosodic phenomenon in continuous speech and (2) emphasis can be better understood by degree of contrast.

Index Terms: perceived emphasis, temporal features, overall tempo, discourse structure, normalization, continuous speech