What is Charisma?

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Computational Linguistics Analysis
of Charismatic Speech:
Cross-Cultural and Political
Perspectives
Andrew Rosenberg
NLP & Psychology
11/12/2015
Collaborators
• original slides by Julia Hirschberg
• Erica Cooper, Svetlana Stenchicova Stoyanchev,
Wisam Dakka, Aron Wahl, Judd Sheinholtz, Fadi
Biadsy, Rolf Carlson, Eva Strangert, Ian Kaplan,
William (Yang) Wang
Listening Experiment
1
2
3
4
5
Which of these speakers sound charismatic?
1. Vladimir Lenin
2. Franklin D. Roosevelt
4. Warren G. Harding
3. Mao Zedong
5. Adolf Hitler
What is Charisma?
What is Charisma?
• The ability to attract, and retain followers by
virtue of personal characteristics -- not traditional
or political office (Weber ‘47)
– E.g. Gandhi, Hitler, Castro, Martin Luther King Jr.,..
– Personalismo
• What makes an individual charismatic? (Bird ’93,
Boss ’76, Dowis ’00, Marcus ’67, Touati ’93,
Tuppen ’74, Weber ‘47)
– Their message?
– Their personality?
– Their speaking style?
What is Charismatic Speech?
• Circularly…
– Speech that leads listeners to perceive the speaker as
charismatic
• What aspects of speech might contribute to the
perception of a speaker as charismatic?
– Content of the message?
– Lexico-syntactic features?
– Acoustic-prosodic features?
Our Goals
• Understand which aspects of speech are correlated
with observer perceptions of charisma
• To identify charismatic in political leaders –
current and future
• To create more charismatic text-to-speech
synthesizers
Our Approach
• Collect tokens of charismatic and non-charismatic
speech from a small set of speakers on a small set
of topics
• Ask listeners to rate the ‘The speaker is
charismatic’ plus statements about a number of
other attributes (e.g. The speaker is …boring,
charming, persuasive,…)
• Correlate listener ratings with lexico-syntactic and
acoustic-prosodic features of the tokens to identify
potential cues to perceptions of charisma
Outline
• Charisma in American English political speech
• Comparison with text: what is said vs. how it is
said
• Charisma in Arabic speech
• Cross-cultural perceptions of charisma
• Charisma in recent American politics:
– Democrats in 2008
– Republican today
Outline
• Charisma in American English political speech
• Comparison with text: what is said vs. how it is
said
• Charisma in Arabic speech
• Cross-cultural perceptions of charisma
• Charisma in recent American politics:
– Democrats in 2008
– Republican today
American English Perception Study
• Data: 45 2-30s speech segments, 5 each from 9
candidates for Democratic nomination for U.S.
president in 2004
– Liberman, Kucinich, Clark, Gephardt, Dean, Moseley
Braun, Sharpton, Kerry, Edwards
– 2 ‘charismatic’, 2 ‘not charismatic’
– Topics: greeting, reasons for running, tax cuts, postwar
Iraq, healthcare
– 4 genres: stump speeches, debates, interviews, ads
• 8 subjects rated each segment on a Likert scale (15) 26 questions in a web survey
• Duration: avg. 1.5 hrs, min 45m, max ~3hrs
Results: How Much Do Subjects Agree
with Each Other?
• Over all statements?
– Using Cohen’s) kappa statistic with quadratic weighting, mean  =
0.207
• On the charismatic statement?
•  = 0.232 (8th most agreed upon statement)
• By token?
– No significant differences across all tokens although Edwards and
Liberman tokens show significantly more agreement across all
statements
• By statement?
– Individual statements demonstrate significantly different
agreements (most agreement: The speaker is accusatory, angry,
passionate, intense; least agreement: The speaker is trustworthy,
believable, reasonable, trustworthy)
Results: What Do Subjects Mean by
Charismatic?
• Which other statements are most closely
correlated with the charismatic statement?
(determined by kappa): a functional definition
The speaker is enthusiastic
0.620
The speaker is persuasive
0.577
The speaker is charming
0.575
The speaker is passionate
0.543
The speaker is boring
-0.513
The speaker is convincing
0.499
Results: Does Whether a Subject Agrees with the
Speaker or Finds the Speaker ‘Clear’ Affect
Charisma Judgments
• Whether a subject agrees with a token does not
correlate highly with charisma judgments ( =
0.30)
• Whether a subject finds the token clear does not
correlate highly with charisma judgments ( =
0.26)
Results: Does the Identity of the Speaker
Affect Judgments of Charisma?
• There is a significant difference between speakers
(p=2.20e-2)
• Most charismatic
– Rep. John Edwards (mean 3.86)
– Rev. Al Sharpton (3.56)
– Gov. Howard Dean (3.40)
• Least charismatic
– Sen. Joseph Lieberman (2.42)
– Rep. Dennis Kucinich (2.65)
– Rep. Richard Gephardt (2.93)
Results: Does Recognizing a Speaker
Affect Judgments of Charisma?
• Subjects asked to identify which, if any, speakers
they recognized at the end of the study.
• Mean number of speakers believed to have been
recognized, 5.8
• Subjects rated ‘recognized’ speakers as
significantly more charismatic than those they did
not believe they had recognized (mean 3.39 vs.
mean 3.30).
Results: Does Genre or Topic Affect
Judgments of Charisma?
• Recall that tokens were taken from debates,
interviews, stump speeches, and campaign ads
– Genre does influence charisma ratings (p=.0004)
• Stump speeches were the most charismatic (3.38)
• Interviews were the least (2.96)
• Topic does affect ratings of charisma significantly
(p=.0517)
– Healthcare > post-war Iraq > reasons for running
neutral > taxes
What makes Speech Charismatic?
Features Examined
• Duration (secs, words, syls)
• Charismatic speech is
personal: Pronoun density
• Charismatic speech is
contentful: Function/content
word ratio
• Charismatic speech is simple:
Complexity: mean
syllables/word (Dowis)
• Disfluencies
• Repeated words
• Min, max, mean, stdev F0
(Boss, Tuppen)
– Raw and normalized by
speaker
• Min, max, mean, stdev
intensity
• Speaking rate (syls/sec)
• Intonational features:
– Pitch accents
– Phrasal tones
– Contours
Results: Lexico-Syntactic Correlates of
Charisma
• Length: Greater number of words positively correlates with
charisma (r=.13; p=.002)
• Personal pronouns:
– Density of first person plural and third person singular pronouns
positively correlates with charisma (r=.16, p=0; r=.16, p=0)
– Third person plural pronoun density correlates negatively with
charisma (r=-.19,p=0)
• Content: Ratio of adjectives/all words negatively correlates
with charisma (r=-.12,p=.008)
• Complexity: Higher mean syllables/word positively
correlates with charisma (p=.034)
• Disfluency: greater % negatively correlates with
charisma (r=-.18, p=0)
• Repetition: Proportion of repeated words
positively correlates with charisma (r=.12, p=.004)
Results: Acoustic-Prosodic Correlates of
Charisma
• Pitch:
– Higher F0 (mean, min, mean HiF0, over male speakers)
positively correlates with charisma (r=.24,p=0;r=.14
p=0;r=.20,p=0)
• Loudness: Mean rms and sdev of mean rms
positively correlates with charisma
(r=.21,p=0;r=.21,p=0)
• Speaking Rate:
– Faster overall rate (voice/unvoiced frames) positively
correlates with charisma (r=.16,p=0)
• Duration: Longer duration correlates positively
with charisma (r=.09,p=.037)
• Length of pause: sdev negatively correlates with
charisma (r=-.09,p=.004)
Summary for American English
• In Standard American English, charismatic
speakers tend to be those also highly rated for
enthusiasm, charm, persuasiveness, passionateness
and convincingness – they are not thought to be
boring
• Charismatic utterances tend to be longer than
others, to contain a lower ratio of adjectives to
all words, a higher density of first person plural
and third person singular pronouns and fewer
third person plurals, fewer disfluencies, a
larger percentage of repeated words, and more
complex words than non-charismatic utterances
• Charismatic utterances are higher in pitch (mean,
min) with more regularity in pause length,
faster, louder with more variation in intensity
Outline
• Charisma in American English political speech
• Comparison with text: what is said vs. how it is
said
• Charisma in Arabic speech
• Cross-cultural perceptions of charisma
• Charisma in recent American politics:
– Democrats in 2008
– Republican today
Replication of Perception Study from Text Alone
• Lower statement agreement, much less on
charismatic statement, different speakers
most/least charismatic (Clark most, Sharpton
least)
• `Agreement with speaker’, genre and topic had
stronger correlations with charisma
• Lexico-syntactic features show weaker
correlations
– 1st person pronoun density negatively correlated and
complexity not at all
– Similar to speech experiment for duration,
function/content, disfluencies, repeated words
Outline
• Charisma in American English political speech
• Comparison with text: what is said vs. how it is
said
• Charisma in Arabic speech
• Cross-cultural perceptions of charisma
• Charisma in recent American politics:
– Democrats in 2008
– Republican today
Hypothesis: Perception of Charisma Differs by
Culture
• People of different languages and cultures
perceive charisma differently
• In particular, they perceive charismatic speech
differently
– Do Arabic listeners respond to American politicians the
same way Americans do?
– Do Americans respond to Arabic politicians the way
Arabs do?
Palestinian Arabic Perception Study
• Same paradigm as for SAE
• Materials:
– 44 speech tokens from 22 male native-Palestinian
Arabic speakers taken from Al-Jazeera TV talk shows
– Two speech segments extracted for each speaker from
the same topic (one we thought charismatic and one
not)
• Web form with statements to be rated translated
into Arabic
• Subjects: 12 native speakers of Palestinian Arabic
How Does Charisma Differ in Arabic?
• Subjects agree on judgments a bit more (κ=.225)
than for English (κ=.207) but still low
– Agree most on clarity of msg, enthusiasm, charisma,
intensity – all differing from Americans
– Agree least on desperation (as SAE), friendliness,
ordinariness, spontaneity of speaker
– Charisma statement correlates (positively) most
strongly with speaker toughness, powerfulness,
persuasiveness, charm, and enthusiasm and negatively
with boringness
• Role of speaker identity important in judgments of
charisma in Arabic as in English
– Most charismatic speakers: Ibrahim Hamami (4.75),
Azmi Bishara (4.42), Mustafa Barghouti (4.33)
– Least: Shafiq Al-Hoot (3.10), Mohammed Al-Tamini
(3.42), Azzam Al-Ahmad (3.33)
– Raters claimed to recognize only .55 (of 22) speakers
on average, perhaps because the speakers were less well
known than the Americans
• Topic important in charisma ratings (r=0,p=.043)
Israeli separation wall > assassination of Hamas leader >
debates among Palestinian groups > the Palestinian
Authority and calls for reform > the Intifada and
resistance
Lexical Cues to Charisma
• Length in words positively correlates with
charisma, as for Americans
• Disfluency rate negatively correlates, as for
Americans
• Repeated words positively correlates with
charisma, as for Americans
• Presence of Arabic ‘dialect markers’ (words,
pronunciations) negatively correlates with
charisma
• Density of third person plural pronouns positively
correlates w/ charisma – differing from Americans
Acoustic/Prosodic Cues to Charisma
• Duration positively correlated with charisma, as
for Americans
• Speaking rate approaches negative correlation –
opposite from American
– But rate of the fastest intonational phrase in the token
positively correlated for both languages
– Sdev of rate across intonational phrases positively
correlated for charisma in Arabic
• Pauses
– #pauses/words ratio positively correlated with charisma
but not for Americans
– Sdev of length of pause positively correlated in Arabic
but negatively for Americans
• Pitch:
– Mean pitch positively correlates (as for Americans) but
also F0 max and sdev
– Min pitch negatively correlates (opposite from
Americans)
• Intensity: Sdev positively correlates w/ charisma
Outline
• Charisma in American English political speech
• Comparison with text: what is said vs. how it is
said
• Charisma in Arabic speech
• Cross-cultural perceptions of charisma
• Charisma in recent American politics:
– Democrats in 2008
– Republican today
How Are Perceptions of Charisma Similar Across
Palestinian and Arabic Cultures?
• Level of subject agreement on statements
• Role of speaker ID, topic in charisma judgments
• Positive correlations with charisma
– Mean pitch and range
– Duration, repeated words
– Speaking rate of fastest IP
• Negative correlations with charisma
– Disfluencies
How Do Charisma Judgments Differ Across
Cultures?
• Statements most and least agreed upon
• For Arabic vs. English:
– Positive correlations with charisma
• Sdev of speaking rate, pause/word ratio, sdev of
pause length, F0 max and sdev, sdev intensity
– Negative correlations with charisma
• Dialect, density of third person plural pronouns
• Speaking rate, min F0
Ratings Within and Across Cultures
• Cross-cultural comparison of subjects ratings:
– American raters/Arabic speech
– Palestinian raters/English speech,
– Swedish raters/English speech
• Do native and non-native raters differ on mean
scores per token?
• Yes, Eng/Pal rating English, Swe/Pal rating English
• Do mean scores correlate per token?
• Yes, for all
• Amer and Swe rating English:
– paired t-test betw means per token: p-value = 0.03064
– cor between means of rater-normalized ratings: r = 0.60, p-value =
1.170e-05
• Amer and Pal rating English:
– paired t-test betw means: p-value = 0.1048
– cor between means of rater-normalized ratings: r = 0.47, p-value =
0.0009849
• Amer and Pal rating Arabic:
– paired t-test betw means: p-value = 0.00164
– cor between means of rater-normalized ratings: r = 0.72, p-value =
3.049e-08
• Swe and Pal rating English:
– paired t-test betw means: p-value = 0.8479
– cor between means of rater-normalized ratings: r = 0.55, p-value =
9.467e-05
Charisma and Politics
Can we predict the Winners?
or
The Losers?
Goals and Research Questions
• Investigate emotion and charisma in political
discourse
– Collect a corpus of political speech: debates
– Determine lexical and acoustic correlates of political
success: correlate with subsequent polls
– Characterize similarities and differences between
Democrats and Republicans
Corpus Collection
• Democratic primaries from 2008:
– Biden, Clinton, Dodd, Edwards, Gravel, Kucinich,
Obama, Richardson
– New Hampshire MSNBC Debate, September 26, 2007
• Fall 2011 Republican primaries:
– Bachmann, Cain, Gingrich, Huntsman, Johnson, Paul,
Perry, Romney, Santorum
– Fox News / Google Debate, September 22, 2011
• Interviews for all candidates
Gallup Poll Results
Democrats
Poll Results
Republicals
Poll Results
Clinton
47%
Romney
20%
Obama
26%
Cain
18%
Edwards
11%
Perry
15%
Richardson
4%
Paul
8%
Biden
2%
Gingrich
7%
Dodd
1%
Bachmann
5%
Kucinich
1%
Santorum
3%
Gravel
0.5%
Huntsman
2%
Johnson
0%
Lexical Features
• For Debate speech only
–
–
–
–
–
–
–
Word Count
Laughter, applause, and interruptions
Number of speaker turns
Average number of words per turn
Syllables per word
Disfluencies per word
Linguistic Inquiry and Word Count (LIWC) features
Acoustic Features
• Debates and Interviews: mean, min, max, and
standard deviation of f0
• Difference for these values between debates and
interviews
Results: Corrlates with Post-Debate Poll
Standing
Features
Democracts
Republicans
Word Count
Laughs
Applause
Turns
Interruptions
Avg Words Per Turn
Avg Syllables Per Word
Disfluencies Per Word
Mean-f0 Difference
Min-f0 Difference
0.804
0.084
0.194
0.846
0.052
0.199
0.015
-0.805
0.059
0.002
0.582
0.780
0.350
0.381
0.247
0.406
-0.768
-0.130
0.479
0.105
LIWC Positive Correlates for Democrats
Feature
Examples
Correlates
Insight
Think, know consider
0.74
Inclusive
And, with, include
0.680
Cognitive
Cause, know, ought
0.679
Words per sentece
0.661
Common verbs
Walk, went, see
0.657
Positive emotion
Love, nice, sweet
0.632
Pronouns
I, them, itself
0.626
Nonfluencies
Er, hmm, umm
0.611
LIWC Features: Negative Correlates for
Democrats
Features
Examples
Correlation
Articles
A, an, the
-0.684
All Punctuation
-0.653
Periods
.
-0.639
Dashes
-
-0.595
Numerals
12, 38, 156
-0.581
Questions marks
?
-0.578
Ingestion
Dish, eat, pizza-0.575
-0.575
Money
Audit, cash, owe
-0.548
2nd Person Pronouns
You, your
-0.506
LIWC Features: Correlates for
Republicans
Features
Examples
Correlation
Leisure
Cook, chat, movie
0.869
Past tense
Went, ran, had
0.732
“Other” punctuation
!”:%$
0.665
Dictionary words
0.541
Personal pronouns
I, them, her
0.525
6+ letters
Abandon, abrupt,
absolute
-0.741
Home
Apartment, kitchen,
family
-0.513
General Party Differences
•
•
•
•
•
Democrat audiences laughed more
Republican audience applauded more
Democrats got interrupted more
Republicans had more words per turn
Both had about the same number of syllables per
word
• Democrats' debate speech was more different from
their interviews, but Republicans responded
slightly more positively to these differences.
Conclusions
• Democrats: Talk more, use fewer disfluencies, and
use more Insight words
• Republicans: Make the audience laugh, use
Leisure-related words, and avoid longer words
Historical Political Debates
• Televised presidential debates first held in 1960.
• Then 1976-present.
• Polling information is available from CBS polling
from 1976-present
Predicting debate winners
• Try to predict winners of the current debate given
all prior debates.
– “fighting the last war”
– Only those debates with one democrat and one
republican
– Both VP and Presidential Debates
Debate features
• Word Usage: 1) personal pronouns, 2) number of
questions, 3) pleasantries, 4) contractions, 5)
numbers, 6) references to the opponent, 7)
references to running mate.
• Topic Words: seed WordNet search with “god”,
“health”, “religion, “tax”, and “war”
– WordNet-defined attribute, synonym, antonym,
derivationally-related form, synset entry, troponym,
meronym, member meronym, domain category, of the
seed term and first-degree words added from the seed
term
Debate features
• Affective Content: average and sum of
Dictionary of Affect in Language activation,
imagery & pleasantness
• Named Entities: number of times and rate of
mentions of people, locations and organizations
• Term Vector: tf*idf of the top 10k words
(stemmed, omitting stop words)
• Length-features: syllable, word, sentence length
of turns
• Complexity: Flesch-Kincaid grade readability.
Debate winner prediction results
• Train on all previous
Unsplit
(full debate)
Debate
(full debate)
0.64 (0.68) p=0.75
Split
(predict each 20 turns)
0.61 (0.65) p=1.0
Debater
(only one turn)
0.57 (0.5) p=0.23
0.51 (0.5) p=0.47
Unsplit
(full debate)
• Just 2008
Debate
(full debate)
1.0 (0.68) p=0.21
Split
(predict each 20 turns)
0.72 (0.65) p=0.35
Debater
(only one turn)
0.75 (0.5) p=0.14
0.61 (0.5) p=0.12
Debate Results: Important Features
• First person plural possessives (“our”) used by
Democrats
• “sat”, “estimates”, “plain”, “advocate”, “roughly”
• “atomic”
• Grade level readability of Democrats
• Second person singular object pronouns used by
Republicans
• “disagreements”, “unilateral”, “soviets”
Debate Results: Feature analysis
• First person plural possessives (“our”) used by Democrats
– Negatively correlates with Democratic wins
• Grade level readability of Democrats
– Lower complexity in Democratic wins
• Second person singular object pronouns (“you”) used by
Republicans
– Negatively correlates with Republican wins
• “atomic”, “unilateral”, “soviets”
– important political topics
• “achieve”, “disagreements”
– political action
Future Work
• Investigate additional acoustic features (intensity,
speaking rate, voice quality)
• Higher level prosodic features (intonational
contours, phrasing)
• Lexical features from interviews and debates
• More complicated / interesting lexical features
– Cross-cultural similarities and differences
– Entrainment
• Interpersonal relationships
Thank you!
The Prediction of Charisma
• Arabic
English
Arabic Prosodic Phenomena
MSA vs. Dialect
• A word is considered dialectal if:
– It does not exist in the standard Arabic lexicon
– It does not satisfy the MSA morphotactic constraints
– Phonetically different (e.g., ya?kul vs. ywkil)
• In corpus of tokens
– 8% of the words are dialect.
– 80% of the dialect words are accented.
Arabic Prosody: Accentuation
• 70% of words are accented
• 60% of the de-accented words are function words
or disfluent items
– Based on automatic POS analysis (MADA)
– 12% of content words are deaccented
• Distribution of accent types:
–
–
–
–
H* or !H* pitch accent, 73%
L+H* or L+!H*, 20%
L*, 5%
H+!H*, 2%
Arabic Prosody: Phrasing
• Mean of 1.6 intermediate phrases per intonational
phrase
• Intermediate phrases contain 2.4 words on average
• Distribution of phrase accent/boundary tone
combinations
–
–
–
–
–
L-L%
H-L%
L-H%
H-L%
H-H%
59%
26%
8%
6%
1%
Arabic Prosody – most common contours
H* LH* HL+H* LH* H* LH* !H* LL* LL+H* !H* LH* H* HH* !H* !H* LL+H* H-
21.9
13.4
9.7
7.6
4.1
4.1
3
3
2.3
2.1
Arabic Prosody – Disfluency
• In addition to standard disfluency:
– Hesitations
– filled pauses
– self-repairs
• In Arabic, speakers could produce a sequence of all of the
above. (see praat: file: 1036 and 2016)
• Disfluency may disconnect prepositions and conjunctions
from the content word:
– ‫ تأتي‬... ‫ يعني‬... ‫ لـ‬... ‫ولتأتي => و‬
– w- l- uh- yEny uh- t?ty instead of wlt?ty
Functional Definition of
Charisma
• According to our 12 native American English
(AE) speakers who rated AE speech, “charisma
is”
Analyzing Charismatic Speech
Functional Definition of
Charisma
• According to our 12 native Palestinian Arabic
(PA) speakers who rated PA speech, “charisma is”
Examples of features that
correlate with Charisma
• Variation in length of pauses: negative correlate in
English but positive in Arabic
• Speaking Rate: positive correlate in English and
approaching negative correlate in Arabic
• Mean Pitch: positive correlate in both studies
Examples of features that
correlate with Charisma
• High variation in loudness: positive correlate in Arabic
• Disfluency: rate of disfluencies (repetitions, repairs, and
filled pauses) negatively correlated with charisma in both
• First person plural pronoun: positive correlate in English
only
• Ratio of adverbs and adjectives to number of words in
utterance: negative correlate in English
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