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Lecture 4: Emotion’s relation to mental processes (judgment and decision-making)
Goals
Give some examples of why important to model
human decision-making
Review rational choice theory (current best model)
Illustrate “emotional” departures from RCT
Provide framework for organizing various ways that
emotion departs from RCT predictions
Experiment
Guest lecture on NeuroscienceGilly KoritzkyBrain and Creativity Institute
Emotion and Rationality
Emotion is often said to “distort” reason. What
does that mean?
It means there is a theory of people “should” make
decisions (Rational Choice Theory)
– Follows from a set of principles that seem an irrefutable
characteristic of good decision-making
And people don’t follow that theory
And emotions help explain departures from
rational choice theory
Why should we care that people not “rational”
Rational models are used to predict human decisions and
make policy decisions across wide range of applications
– Economic decisions: how individuals buy and invest
– Public policy decisions: how will programs impact the happiness and
well-being of populations
– Consumer choice: will consumers be satisfied by a product
– Market mechanisms design: will policies governing transactions in an
online marketplace be efficient
– Technology acceptance
Rational models are used to guide automated systems
– Bargaining agents
– Security agents
– Navigation systems
Example: Security
Milind
Tambe
Rational models (game theory) can help us build
decision-aids for such efficient security resource
allocation. Use computational methods to predict
the decision-making of potential criminals
Example: Navigation
Sarit Kraus
Rational models can help us recommender systems such
as driver navigation systems. Challenge is to recommend
high quality routes that satisfy user preferences while
achieving other goals (energy efficiency)
Rational Choice Theory
Developed over centuries
Central foundation of economic decision-making
Serves two basic purposes– Normative: how people (and machines) should act and think
Helps us avoid confused, poor thinking
Helps us analyze arguments
Aids in design of “optimal” artificial decision-makers
– Descriptive: how people (and machines) actually act and think? Fundamental postulate of economics: people act rationally
(allows that individuals may not be rational but this can be viewed as noise so that the
population will act rationally)
Variants of Rational Choice Theory
Decision theory centers on cost-benefit
calculations that individuals make without
reference to anyone else’s plans
Game theory analyzes how people make choices
based on what they expect other individuals to do.– We will discuss this when we consider social emotions
Axioms of Decision-Theory
Completeness:
– All actions (or objects) can be ranked in an order of preference;
indifference between two or more alternatives is possible
Transitivity: – If action (or object) a1 is preferred to action a2 and action a2 is preferred
to a3, then a1 is preferred to a3.
Tesla Model S BMW M6
AMC Pacer
Axioms of Decision-Theory
Continuity:
– When there are three lotteries (X, Y and Z), X preferred to Y and Y
preferred to Z, then there should be a mixture of X and Z such that an
individual is indifferent between this mix and Y
Independence:– If we mix two lotteries (X, Y) with a third one, the preference ordering
of the two mixtures will not change (is independent of) the particular
third lottery used
90% + 10% = 100%
50% + 50% 50% + 50%
Decision Theory (or Expected utility theory)
Decision framework that satisfies these axioms
Outcomes can be described by a utility function– The value (or happiness) derived from achieving this state
– E.G. Money could be a person’s measure of happiness
The value of winning a $1,000,000 lottery ticket is $1,000,000
Outcomes can be described by a probability fn.– The likelihood that this state might be achieved in the future
Decisions are then driven by Expected Utility
B
Utility1
Utility2
Utility3
2
Utility6
2
Utility4
Utility5
1
Decision Point
Chance Event
Decision Theory: people utility maximizers
Utility Theory doesn’t assume money is people’s utility function
People assign utility to money. Different people have different utility fn.
Money not necessarily equal to happiness
Daniel Bernoulli 1738
Utility is
the “anticipated pleasure” of wealth
rather than wealth per se
14
Utility Theory doesn’t assume money is people’s utility function
People assign utility to money. Different people have different utility fn.
Utility value
Monetary value
This allows us to capture certain attitudes
towards risk
Money not necessarily equal to happiness
15
People have one of three attitudes toward risk. People can be risk avoiders,
risk seekers (or risk lover) , or indifferent toward risk (risk neutral).
Monetary
Value
Utility Value
Risk avoider
Risk lover
Risk neutral
Utility of money shown for different types of people. Note that for equal
increments in dollar value the utility either rises at a decreasing rate (avoider),
constant rate or increasing rate (lover).
Key point: Absolute value of outcome not important. It is feeling this evokes
Summary: Rational Choice Theory
Decision theory centers on cost-benefit
calculations that individuals make without
reference to anyone else’s plans
Captures many aspects of how people make
decisions (maximize pleasure)
Core assumption underling most economic theory
and economic decision
Core assumption underlying most artificially
intelligent systems
Is Expected Utility a good model of human choice?
Test
Test
50% + 50% 50% + 50%
Influences of Emotion on decision-making(Loewenstein and Lerner 2003)
Start with decision theoryPeople try to maximize expected pleasure (utility)
Decision/
behavior
Expected
consequences
Expected
emotions
Daniel Bernoulli
PROBLEM: If decision theory argues people trying to maximize
future happiness, there are a couple of big problems here
Adam Smith
First problem with equating expected utility with anticipated emotion
Human estimates of future
happiness violate the axioms of
decision-theory
Expected emotions: Risk
Expected emotions are shaped by uncertainty (risk) in ways
not predicted by utility theory
People overweigh small probabilities
People underestimate large probabilities
Losses Loom larger than gains
Maximize
Expected
Utility
ProbabilityExpected
emotions
Prospect TheoryKahneman & Tversky, 1979
Relaxes the independence assumption
– Distinguishes subjective from objective probability: People overweigh small
probabilities and underestimate large ones
– People assign different utility to losses and gains
Maximize
Expected
Utility
ProbabilityExpected
emotionsS
ub
jecti
ve
pro
ba
bil
ity
Probability
function
Utility
function
Probability bias shaped by fear
Su
bje
cti
ve p
rob
ab
ilit
y
Probability
function
Another Test
Again, most people’s preferences violate the
independence assumption
Expected emotions: Regret
Expected emotions are shaped by our regret over what might
have happened
Maximize
Expected
Utility
ProbabilityExpected
emotions
Mellers (1997) decision affect theory
Assume play lottery with outcomes A and B. A occurs
RegretA ≈ UtilityA + d(UtilityA – UtilityB) (1 – ProbA)
Where d is a “disappointment function”
Argues people try to minimize regret
Second problem with equating expected utility with anticipated emotion
Humans are bad at forecasting how
they will feel in the future
(estimated happiness ≠ experienced happiness)
It seemed a good idea at the time…
Affective forecasting
People not so good at forecasting – What: what emotion they will feel following a decision
– How much: the intensity of the experience
– How long: the duration of the emotion
People fail to account for their ability to cope
– Become desensitized to positive circumstances
– Become resigned to negative circumstances
People overweigh outcomes in immediate focus
– E.g., Students in mid-west predicted they would be happier moving to
California; students in California predicted they’d be less happy in mid-
west; yet both equally happy
Affective forecasting (see guest lecture)
Some evidence that there are two distinct
mechanisms for forecasting
– Simulation route:
Vividly imagine being in a certain situation
“read” our bodily reactions to that situation (Damasio’s somatic
marker hypothesis)
– Reasoning route:
Reason about emotions: e.g., I expect I would feel this way
Evidence that the “reasoning” approach more suspect to mis-
forecasting effects
MacInnis. Whan. "Looking through the crystal ball: Affective forecasting and misforecasting in
consumer behavior." Review of Marketing Research 2 (2005): 43-80.
One proposed solution
Expected emotions are time dependent: care less about
events far in the future (explains procrastination?)
Can be modeled with hyperbolic discounting
Make utility a
function of time
Decision/
behavior
Expected
consequences
Expected
emotions
Expected emotions violate axioms of EU
– Prospect theory
– Regret theory
Expected emotion ≠ experienced emotion
– Hyperbolic discounting
Summary of first set of challenges
But that’s not all….
Immediate influences
Maximize
Expected
Utility
Probability UtilityImmediate
emotions
Current emotions changes the decision procedure
Negative emotions narrow intentional focus (on potential threats) and deeper processing of threats
Question pre-conceptions, second guessing
Slower decision making
Positive emotions broaden attentional focus
Shallow processing, quick decisions
Uncritically accept initial judgments/stereotypes
Immediate influences
Maximize
Expected
Utility
Probability UtilityImmediate
emotions
Low intensity emotions
Inform cognition (Affect as information – Clore)
Easily suppressed/overcome if aware of them
High intensity emotions
Can overwhelm cognition. People report being “out of control”
Eg. Phobicsreport there is nothing to fear but are helpless to act on that
awareness
AngerLerner&Tiedens06:
Portrait of the angry
decision maker
Anticipatory influences
Maximize
Expected
Utility
Probability Utility
Anticipatory
influences
Immediate
emotions
Anticipated emotions change our immediate
emotions
Incidental influences
Maximize
Expected
Utility
Probability Utility
Anticipatory
influences
Unrelated events can influence our immediate
emotions
– Sunny day
– Happy or sad music
– Disgusting room
Incidental
influences
Immediate
emotions
EmotionAction
Tendencies“Affect”
PhysiologicalResponse
EnvironmentGoals/Beliefs/
Intentions
Appraisal Tendencies Framework (Han, Lerner, Keltner 2007.)
Desirability
Controllability
Causal Attribution
Emotion
Withdraw Sadness Lo Arousal
EnvironmentGoals/Beliefs/
Intentions
UNDESIRABLE
UNCONTROLABLE
BLAMEWORTHY
EmotionAction
Tendencies“Affect”
PhysiologicalResponse
EnvironmentGoals/Beliefs/
Intentions
Appraisal Tendencies Framework (Han, Lerner, Keltner 2007.)
Desirability
Controllability
Causal Attribution
Emotion
Withdraw Sadness Lo Arousal
EnvironmentGoals/Beliefs/
Intentions
UNDESIRABLE
CONTROLABLE
BLAMEWORTHY
APPROACH ANGER Hi Arousal
EmotionAction
Tendencies“Affect”
PhysiologicalResponse
EnvironmentGoals/Beliefs/
Intentions
Appraisal Tendencies Framework (Han, Lerner, Keltner 2007.)
Desirability
Controllability
Causal Attribution
Emotion
APPROACH ANGER Hi ArousalWithdraw Sadness Lo Arousal
EnvironmentGoals/Beliefs/
Intentions
UNDESIRABLE
CONTROLABLE
BLAMEWORTHY
UNCONTROLABLE
Summary
People don’t follow rational choice theory
Good mathematical models of some departures– E.g. prospect theory; discounting functions
Not so go mathematical models of others– Though appraisal theory (ATF) gives us some insight
Some influences integral to the situation– And therefore probably sensible adaptations
Some incidental– And therefore hard to argue that they are beneficial
Human Emotions in Decision-Making:
The Somatic Marker Hypothesis
Presented by Gilly Koritzky, Ph.D.
Brain and Creativity Institute
University of Southern California
Most of us are taught from early on that sound decision can only be based on logical, rational thinking.
- Emotion can only cloud the mind and interfere with good judgment.
- “Don’t get all emotional! Be rational!”
But there is evidence to suggest that “rational” decision making in fact depends on prior accurate emotional processing.
A Brief History
Phineas P. Gage (1823–1860), an American railroad construction
foreman, who survived a rock blasting accident in which a large iron rod
was driven completely through his head, destroying much of his brain's
left frontal lobe.
Before the accident, Phineas Gage was a man of normal intelligence, responsible, sociable, and popular among peers and friends.
He survived this accident with normal intelligence, memory, speech, sensation, and movement.
However, his (social) behavior changed completely: “ The equilibrium or balance between his intellectual faculties and animal propensities, seems to have been destroyed…
“ fitful, irreverent…
“ manifesting but little deference for his fellows…
“ impatient of restraint or advice when it conflicts with his desires…
“ obstinate, yet capricious and vacillating…
“In this regard his mind was radically changed, so decidedly that his friends and acquaintances said he was "no longer Gage".”
A Brief History
What region of Gage’s brain was damaged by the rod?
Many years later, scientists generated a computer modelling with the exact
dimensions of Gage’s skull.
Parietal, Temporal, and mid-brain areas, responsible for sensory and motor
function, speech, and memory were intact.
As can be seen, only the frontal lobe was affected.
Or, more precisely: the orbitofrontal cortex.
Patients with lesions in the
Ventro-Medial (Orbital) Prefrontal Cortex
Normal intelligence, But:
• Severe impairments in judgment and decision-making in real-life - In the financial domain (bankruptcies). - In the social domain (involvement with unscrupulous people). - Loss of close relationships, marriage, family, and friendship.
• Abnormalities in emotion Compromised ability to express emotion and to experience feelings in appropriate social situations.
An influential neural theory of decision-making, the Somatic Marker Hypothesis (SMH).
Emotion-related signals (somatic markers) assist cognitive processes in implementing decisions.
These somatic markers can be non-conscious: they can bias behavior even when a person is not really aware of them.
The Somatic Marker Hypothesis
(Antonio Damasio & Antoine Bechara)
Definitions:
EMOTION. A collection of physiological changes in body and brain states
triggered in response to an event.
Somatic Marker Hypothesis (SMH)
Definitions:
EMOTION. A collection of physiological changes in body and brain states
triggered in response to an event.
heart rate, skin conductance, endocrine release,
skin color, body posture, facial expression.
Feeling. What the individual senses or subjectively reports.
Somatic Marker Hypothesis (SMH)
Emotion “I have a bad
feeling about
this…” Signals sent to the forebrain
Testing the Somatic Marker Model:
The Iowa Gambling Task (IGT) paradigm for measuring decision-making
(Bechara, Damasio, Damasio, & Anderson)
Iowa Gambling Task (IGT)
DD
Gain per Card
$100
$1250
-$250
$100
$1250
-$250
$ 50
$250
+$250
$ 50
$250
+$250
AA BB CC
“Bad” Decks “Good” Decks
Loss per 10 Cards
Net per 10 Cards
5 sec
Onset of Card Selection
ANTICIPATORY SCR
(Before Choice)
REWARD/ PUNISHMENT SCR
(After Choice)
(a)
(b) Skin Conductance Response (SCR)
Bechara et al., 1994
The physiological measurement indicates that anticipatory emotion is
critical for good decision-making in many settings
What can we learn from all this about how computers can better
understand, sense, or simulate human behavior?
<discussion>
Modulating Factors
One of the fundamental questions in decision-making research is
how humans assign value to options.
Time: information conveying immediacy (e.g. getting a heart
disease tomorrow) exerts a stronger influence on decisions than
information conveying delayed/future outcomes (e.g. getting a
heart disease 20 years from now).
Probability: information conveying certainty exerts a stronger
influence on decisions than information about low-probability
outcomes.
Tangibility: information conveying tangibility exerts a
stronger influence on decisions than information about abstract,
intangible outcomes (easier to spend money on credit cards as
opposed to spending “real money”).
- - + + + Immediacy Delay
DA
5-HT
AC DLPC
VMPC A
Insula
Hy
p
Striatum
Reflective
Impulsive
a. b. c.
What if the same event triggers several, different responses?
Examples:
Immunizations, safety equipment (helmets)
- - + + + Immediacy Delay
DA
5-HT
AC DLPC
VMPC A
Insula
H
yp
Striatum
Reflective
Impulsive
a. b. c.
The mechanisms that determine the nature of this overall somatic state (i.e., being positive or negative) are consistent with the principles of natural selection: survival of the fittest.
Stronger somatic markers gain selective advantage over weaker ones.
The final decision is determined by the relative strengths of the pain/pleasure signals.
Is Emotion Always Beneficial for Decision-Making?
Emotions play a major role in the interaction between environmental conditions and human decision processes.
Our neural systems carry emotional signals, which provide valuable knowledge for making fast and often advantageous decisions.
But sometimes, these emotional signals interfere with rational decisions.
Thus, the challenge is:
- To discover the circumstances in which emotions can be either useful or disruptive
- To use reasoned coupling of circumstances and emotions as a guide to human decisions.
Project thoughts
If PhD Student– Great to work on a topic related to thesis (assuming it is related to
emotion)
– Ideally work with another classmate from different research group (but
not required)
– Strongly encouraged to work in group (but not required)
Possible topic (modeling)
Moving beyond laboratory data– Learning from NFL games
Twitter data on “excitement” of ~400 games
Predicting excitement from game structure
– Learning from blog data
“Ground-zero mosque” blogs
Examining role of sacred values
Learning temporal dynamics– Emotions in unfolding situations
– Grit and resilience (persistence in face of failure)
Possible topic (modeling)
Decision-making in “games”– Have lots of data on people’s behavior in various decision games. Would
like to model their data and emotional responses
Other
Yo
u
Possible topic (Recognition)
Recognizing mental state (Video)– Have lots of data on people’s behavior in various decision games. Would
like to model their data and emotional responses
Possible topic (Recognition)
Recognizing mental state (Audio)– Have lots of data on people’s behavior in various decision games. Would
like to model their data and emotional responses
“Serious games”
Other
Yo
u
“Not so serious games”
EmotionAction
Tendencies“Affect”
PhysiologicalResponse
EnvironmentGoals/Beliefs/
Intentions
Desirability
Controllability
Causal Attribution
