This article reviews the evidence for rhythmic categorization that has emerged on the basis of rhythm metrics, and argues that the metrics are unreliable predictors of rhythm which provide no more than a crude measure of timing. It is further argued that timing is distinct from rhythm and that equating them has led to circularity and a psychologically questionable conceptualization of rhythm in speech. It is thus proposed that research on rhythm be based on the same principles for all languages, something that does not apply to the widely accepted division of languages into stress- and syllable-timed. The hypothesis is advanced that these universal principles are grouping and prominence and evidence to support it is provided.

Many theories of intonational phonology have granted some special status to pitch features that occur at the edges of prosodic domains, contrasting them with prominence-lending pitch configurations. The standard American structuralist theory that flourished in the 1950s (Trager & Smith 1951) drew a clear distinction between PITCH PHONEMES and JUNCTURE PHONEMES, the former constituting the body of a contour and the latter describing the movements at the contour’s end. Parallel to this development, a distinction was also drawn within the Prague School between the cumulative and delimitative functions of tonal phenomena (Trubetzkoy 1958), the former including prominence, the latter domainedge marking. Bolinger (especially 1970) distinguished ‘accent’ from ‘intonation’: ACCENT referred to the distinctive pitch shapes that accompany prominent stressed syllables (now generally known, following Bolinger, as pitch accents), while INTONATION included, among other things, distinctive pitch movements at the ends of contours. A distinction very similar, but not identical, to Bolinger’s is made in the theory of intonation developed at the Institute for Perception Research (IPO) in the Netherlands (Cohen & ’t Hart 1967, ’t Hart et al. 1990), namely between PROMINENCE-LENDING and NON-PROMINENCE-LENDING pitch movements.

This chapter provides an analysis of the prosodic and intonational structure of Greek within the autosegmental/metrical framework of intonational phonology, and presents Greek ToBI (GRToBI), a system for the annotation of Greek spoken corpora based on this analysis. Both the analysis and the annotation system have largely been developed on the basis of a corpus of spoken Greek. The analysis posits five pitch accents (H*, L*, H*+L, L*+H, L+H*), and two levels of phrasing, the intermediate phrase (ip) and the intonational phrase (IP), which are tonally demarcated by three types of phrase accent (H-, L-, !H-) and three types of boundary tone (H%, L%, !H %) respectively. Unlike the original ToBI, GRToBI has five tiers: the Tone Tier, the Words Tier, the Break Index Tier, the Miscellaneous Tier, and the Prosodic Words Tier (a phonetic transcription of prosodic words).

This study presents a method for analyzing speech rhythm using empirical mode decomposition of the speech amplitude envelope, which allows for extraction and quantification of syllabic- and supra-syllabic time-scale components of the envelope. The method of empirical mode decomposition of a vocalic energy amplitude envelope is illustrated in detail, and several types of rhythm metrics derived from this method are presented. Spontaneous speech extracted from the Buckeye Corpus is used to assess the effect of utterance length on metrics, and it is shown how metrics representing variability in the supra-syllabic time-scale components of the envelope can be used to identify stretches of speech with targeted rhythmic characteristics. Furthermore, the envelope-based metrics are used to characterize cross-linguistic differences in speech rhythm in the UC San Diego Speech Lab corpus of English, German, Greek, Italian, Korean, and Spanish speech elicited in read sentences, read passages, and spontaneous speech. The envelope-based metrics exhibit significant effects of language and elicitation method that argue for a nuanced view of cross-linguistic rhythm patterns.