Representing Intonational Variation

1. Representing Intonational Variation Julia Hirschberg CS 4706

2. Today • How can we represent meaningful speech variation s.t. we can communicate this to others? • Expanded vs. compressed pitch range? • Louder vs. softer speech? • Faster vs. slower speech? • Differences in intonational prominence? • Differences in intonational phrasing? • Differences in pitch contours?

3. Schemes for Representing Intonational Variation • An early proposal: Joshua Steele • Language Learning Approaches • / IS it INteresting / • / d’you feel ANGry? / • / WHAT’S the PROBlem? / (McCarthy, 1991:106) • How can we capture all and only the meaningful intonational variation for a given language unambiguously?

4. Intonation Models • No commonly agreed upon model for one language, let alone all • Researchers work in different traditions and focus on different aspects of intonation • Different models may arise from different types of data • Auditory • Acoustic • Perceptual • …

5. Intonation Models • Auditory: • ESL-orientated; empirical data scarce; even trained listeners do not always agree on what they hear • Acoustic: • Distinction between linguistically relevant and irrelevant details in acoustic signal • Perceptual approach • Experimental data, often w/ manipulated f0 • Hard to design experiments with naïve listeners which give adequate control over parameters used in making decisions

6. Intonation models • Basic division into linear and superpositional models • Linear models: intonation involves a succession of individual choices from an intonation lexicon • Superpositional models: the intonation of an utterance involves a combination of local and utterance-sized components • Speakers may combine aspects of linear and superpositional models in the production of intonation

7. Intonation Models • Linear or Tone sequencemodels • British school (Kingdon ’58, O’Connor & Arnold ’73, Cruttenden ’97): based on auditory analysis • American School (Pierrehumbert ’80, ToBI): mainly acoustic analysis • Dutch school (‘t Hart, Collier and Cohen 1990): perceptual data • Superpositional models (Fujisaki 1983, Möbius et al. 1993): acoustic/physiological

8. Superpositional models • Pitch pattern of intonation modeled with two components: phrase component and accent component. • Phrase has basic shape, and pitch movements for individual accents are superimposed over basic shape: plus = Apples, oranges and tomatoes

9. Good for modeling declination • Declination: downtrend in f0 over the course of an utterance • Best seen as statistical abstraction: if one takes f0 measurements from enough utterances, over time, a downtrend in f0 will emerge Lily and Rosa thought this was divine. Prince William was gorgeous and he was looking for a bride. They dreamed of wedding bells.

10. Superpositional models • Advantages • Good at modeling declination in intonation languages • Successful in speech synthesis for languages like Japanese (little variation in accent type, e.g.) • Capture prosodic structure in languages which have both tone and intonation (e.g. Mandarin) • Disadvantages • All contours must be modeled with an accent and a phrase component • Many SAE contours cannot be captured easily

11. Intonation contours cannot be modeled as sequences of prosodic events • No account of different accent types, or variations in phrase endings • No notation system which allows users to share observations from large speech corpora or to compare contours • A method primarily for synthesis, analysis of speech production

12. Tone sequence models • General assumption: intonation is generated from sequences of (possibly) categorically different and phonologically distinctive accents • Two types of models within the group of tone sequence models: Type 1: Intonation made up of sequences of pitch movements Type 2: Intonation made up of sequences of pitch levels or targets

13. a a t t r r g g e e t t Two types of tone-sequence model Type 1: based on pitch movements Type 2: based on pitch levels H The British School The Dutch School L The American School

14. Tone Sequence Models • Overall shape of intonation phrase is not component of models • Model is a succession of independent accent and boundary tone choices from an intonation lexicon • Do not model phrase-level phenomena (e.g. declination, pitch range, nuclear accent)

15. The British School • Tone sequence model and pitch movement analysis (e.g.falling vs. rising intonation) • Auditory model: teaching English as a second language • O’Connor and Arnold 1972: • Earliest textbook for English instruction that tells user which contour appropriate in which context • No empirical evidence • British school analyses applied to English, German, Dutch, French, …

16. Concepts in the British School • Basic unit of intonational description: intonation phrase (tone unit) • Delimited by pauses, phrase-final lengthening, pitch movement • Syllables within a tone unit can be stressed or accented • telephone • Accented syllables are stressed and pitch prominent

17. Accent Stressed syllable has full vowel and is perceived as involving a rhythmic beat Pitch prominence • syllable produced with moving pitch or • syllable part of a pitch jump from a preceding syllable or onto a following syllable or • syllable at a point in the utterance where the direction of pitch movement changes (e.g. from rising to falling)

18. Pitch Prominence • Syllable produced with moving pitch • Syllable part of a pitch jump from a preceding syllable or onto a following syllable • Syllable at a point in utterance where direction of pitch movement changes i g r the l g r i l in the gar den the n e d r a g e h t n i l r i g the

19. An example and I think it’sHOrriblerrible you have toCLEANit ...aPOINTwhere There’s a point where you have to clean it and I think it’s horrible...

20. Intonation Phrase Structure • Intonational phrases have an internal structure • Structure determined by location of accents in an IP • Each accent defines the beginning of a prosodic constituent

21. Intonation phrase structure • Two types of accent unit in the British School: • Prenuclear accent units; also called the Head • Nuclear accent units; also called the Nucleus • The nuclear accent unit is the last accent unit in the IP • The head comprises all prenuclear accent units

22. Prenuclear accent unit Nuclear accent unit Prehead Stressed syllable Intonation phrase structure ‘Head’ ‘Nucleus’ But JOHN’s never BEEN to Jamaica

23. a m a i c a c i J a a a J m falling rising m a a i a J c i a c a J m a rising-falling falling-rising a i c m a i a a a c J a J m a level Rising-falling-rising Six nuclear choices in English

24. Strengths and Weaknesses • How are accents, prominence defined? How are they related to segments? Too many options…. • Are prenuclear accents qualitatively different from nuclear accents? What is the evidence? • Does each pitch accent begin a new ‘prosodic unit’ in the phrase? What is the evidence?

25. Next Class • The American School and Laboratory Phonology • ToBI • Read the ToBI conventions • Listen to the ToBI training data or cardinal examples • Bring your laptop and headphones to class