Representing Intonational Variation
Julia Hirschberg
CS 4706
7/15/2016
1
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?
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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?
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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
–…
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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
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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
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Intonation Models
• Linear or Tone sequence models
– 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
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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
=
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Apples, oranges and tomatoes
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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.
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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
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– 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
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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
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Two types of tone-sequence model
Type 1: based on pitch movements
tar
g
et
The British School
The Dutch School
Type 2: based on pitch levels
H
t a rg
e tL
The American School
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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)
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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, …
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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
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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)
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Pitch Prominence
– Syllable produced with moving pitch
i
g
the r l
– Syllable part of a pitch jump from a
preceding syllable or onto a following
syllable
the
g i r l in the gar
den
– Syllable at a point in utterance where
direction of pitch movement changes
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r
a
g
e
h
nt
i
l
r
the g i
n
e
d
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An example
and I think it’s
...a
POINT where
you have to
HOrriblerrible
CLEAN it
There’s a point where you have to clean it and I think it’s horrible...
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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
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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
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Intonation phrase structure
Prenuclear accent unit
Prehead
‘Head’
Nuclear accent unit
‘Nucleus’
Stressed syllable
But JOHN’s never BEEN to Jamaica
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Six nuclear choices in English
mai
a
c
J
a
J a ma
falling
i
a
J a m ca
rising-falling
i a
a
Ja m ca
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Rising-falling-rising
a
c
i
rising
mai a
a
J
c
falling-rising
Ja
m a ic a
level
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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?
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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
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