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					How do we understand
the behavior of others?:
  The agency system




      Clark Barrett
         UCLA

  barrett@anthro.ucla.edu
Heider and Simmel (1944)
               What is agency?
• Agency = the capacity to act in a goal-directed
  (intentional) way

• Humans use the “intentional stance” (Dennett 1987) to
  interpret and make predictions about behavior.

• Main question: What cognitive mechanisms allow us to
  do this?
                     Talk outline
•    Research goal: searching for building blocks of the
     agency system

1.   Perceptual templates / schemas
2.   Conceptual schemas
3.   Switching the system on and off
4.   Interactions with other systems: agency and social
     cognition

•    Concluding speculations
                       Why should you care?

    (Why is the agency system important for culture, norms, and evolution?)


•    A) A security guard fails to detect a terrorist  50 people
     die.
•    B) A security guard throws a grenade into a plane full of
     passengers  50 people die.

•    Perhaps understanding intentions gets you more than just
     looking at outcomes?

(Intentions in behavioral econ: Blount, McCabe)
Decomposing the agency system

   [Ultimate] goal: a computational account
             A “black box” account
               (non-computational)
                “Theory of mind”,
  INPUTS          “Belief / desire    OUTPUTS
                   reasoning”,
               “Intentional stance”

                                        Behavior
Perceptual
                                       predictions
  cues

Knowledge             ?                Judgments &
                                        Decisions



                 What’s in here?
                    Inside the black box
             (a modular, or computational, account)
                                Conceptual schemas
                 Perceptual
 INPUTS          templates /
                                  Predator-prey schema
                  schemas
                         (AD,                                      OUTPUTS
Perceptual               ID)        Social Xch schema
  cues
                                              Etc.
                                                                    Behavior
Knowledge                                                          predictions

                                  Processor (“ToMM”)                Judgments
                                                                    & Decisions


                                Human                John
                  Scope
                                  Dog
                restrictors /                        Susan
                 modifiers             Lion                 Jim

                                Taxa                 Individuals
                    Inside the black box
             (a modular, or computational, account)
                               Conceptual schemas
                 Perceptual
 INPUTS          templates /
                                 Predator-prey schema
                  schemas

                                                                  OUTPUTS
Perceptual                         Social Xch schema
  cues
                                             Etc.
                                                                   Behavior
Knowledge                                                         predictions

                                 Processor (“ToMM”)                Judgments
                                                                   & Decisions


                               Human                John
                  Scope
                                 Dog
                restrictors                         Susan
                                      Lion                 Jim

                               Taxa                 Individuals
              Perceptual templates
• Achieving (many) goals entail
  certain kinds of motion: e.g.,
  pursuit
• If intentions have motion
  signatures, “templates” can be
  made: detectors
• Does the mind contain such
  templates for detecting
  particular kinds of intentional
  behavior?
What basic motion schemas do people
             possess?
  An experimental study of
intentional motion perception
    Todd, Barrett, Miller, & Blythe
        An experimental study of
      intentional motion perception
             Todd, Barrett, Miller, & Blythe

• Question: can people reliably use motion to infer the
  intentions of agents, and categorize them?
• Categories: Pursuit, court, lead / follow, guard, fight, play
• Generated by German adults in game context, evaluated
  by second set of judges (free descriptions, forced
  choice)
• Within categories, no two exemplars alike; must rely on
  abstract qualities to make judgment
    6-category study: German adults
                        0.9
                        0.8
     Percent selected



                        0.7
                        0.6
                        0.5
                        0.4
                         0.3
                         0.2
                         0.1
                           0                                                                       Pl
                                                                                                     ay
                                                                                              Fi
                                                                                        Gu ght
                               ti
                             rsu

                                     urt




                                                                                   Le      a
                                                                                      ad rd
                                              llow
                           Pu

                                    Co




                                                                                C                         Selected
                                                       ard




                                                                          Pu ourt       / fo
                                                               ht
                                           / fo

                                                     Gu

                                                             Fi g


                                                                     y




                                                                            rs               llo
                                                                                                          category
                                                                    Pla




                                                                               uit               w
                                         ad
                                     Le




True category
                                German 3-5 yr olds

                   0.8
                   0.7
Percent selected




                   0.6
                   0.5
                   0.4
                   0.3
                   0.2
                   0.1
                                                                  Play
                     0                                         Lead
                                                       Fight
                           e




                                                                      Selected
                           as



                                   ht
                         Ch




                                                   Chase
                                 Fi g




                                                                      category
                                        ad
                                        Le




                                              y
                                             Pla




 True category
• But:
• Are Germans just communicating a culturally shared
  schema to other Germans?
• Or are these motion schemas universal?
Cross-cultural study: Shuar of Ecuador
Cross-cultural study: Shuar of Ecuador
  4-category cross-cultural study
Categories   Shuar               German

             Shuar adults,       Berlin college   Berlin
             horticulturalists   students         kindergarteners
             N=23                N=40             age 3-5, N=36
Chase        Apapéatin           Verfolgen

Fight        Mániatin            Kämpfen

Lead         Jintíatin           Führen

Play         Nakurústin          Spielen
               Shuar and German adults
        0.9                                                  chase
         0.8                                                 fight
         0.7                                                 lead
         0.6                                                 play
Percent 0.5
selected 0.4
          0.3
          0.2
          0.1
             0
                                                  play
                                as S)
                            fig (G)
                             ch e (




                                              lead
                                     )
                                  (S
                                  as

                                  e




                                  )
                                (G




                                           figh
                               ch



                               ht




                                                         Selected
                               )




                                                t
                             (S
                            ht




                            )




                                         cha
                         fig




                         (G
                         ad




                                             se          category
                        )
                      le




                     (S
                    ad




                   )
                 le


                ay


               (G



      True category
             pl


            ay
         pl
     Motion perception: summary
• There appear to exist motion schemas for particular
  kinds of intention
• The same templates are present across cultures
Conceptual schemas
                           Conceptual schemas
             Perceptual
 INPUTS      templates /
                             Predator-prey schema
              schemas

                                                              OUTPUTS
Perceptual                     Social Xch schema
  cues
                                         Etc.
                                                               Behavior
Knowledge                                                     predictions

                             Processor (“ToMM”)                Judgments
                                                               & Decisions


                           Human                John
               Scope
                             Dog
             restrictors                        Susan
                                  Lion                 Jim

                           Taxa                 Individuals
                           Conceptual schemas
             Perceptual
 INPUTS      templates /
                             Predator-prey schema
              schemas

                                                              OUTPUTS
Perceptual                     Social Xch schema
  cues
                                         Etc.
                                                               Behavior
Knowledge                                                     predictions

                             Processor (“ToMM”)                Judgments
                                                               & Decisions


                           Human                John
               Scope
                             Dog
             restrictors                        Susan
                                  Lion                 Jim

                           Taxa                 Individuals
            Conceptual schemas
• Function: making inferences about particular kinds of
  intentional interaction.
• May be many, e.g. :
   – Social exchange,
   – mating,
   – parent / offspring,
   – predator / prey,
   – kin altruism
   – Fiske: relational models
• Is there evidence for them?
                                       Predator-prey schema

                                                   
                                           Pre-contact




                                         
                    Predator               Mutual          Prey
                    detects prey           detection       detects predator




                         ()                 ()
         Approach               Wait / Flee        Wait / Hide     Hide / Ambush


                                           
Key                                        Pursuit
Agents       Parameters                                               death
 predator    knowledge relation
 prey        action relation
  Study of children’s inferences about
      predator-prey interactions
               Barrett, Cosmides, & Tooby



• Shuar (N=28) and German (N=38) 3 to 5 year olds
• Simulated predator-prey encounter with plastic models
  (Jaguar / horse; Lion / zebra)
• At each stage, children predict what will happen next
• Also infer mental states of predator and prey
                  Example question:
    When the lion sees the zebra, what does the lion
•   Schema-consistent:
                       want to do ?
                                        Schema-
                             100
   – Chase zebra                        inconsistent
                              90        Schema-
   – Catch zebra                        consistent
                              80
   – Bite zebra
                              70
   – Eat zebra
                              60
   – Kill zebra               50
• Inconsistent:               40
   – Go away (N=1 german)     30
   – Eat grass (N=1 shuar)    20
• Rest DK or no response      10

                                 0  r




                                               r




                                                              r
                                  an




                                             an




                                                            an
                                 ua




                                            ua




                                                           ua
                                m




                                           m




                                                          m
                             Sh




                                        Sh




                                                       Sh
                             er




                                        er




                                                       er
                             G




                                        G




                                                       G
                             3 yrs          4 yrs          5 yrs
       Q: When the lion catches the zebra, what will
                         happen?
• Schema-consistent:
   – Lion hurts zebra                100

   – Lion kills and / or eats            90

      zebra                              80

• Inconsistent:                          70

   – German 3yr: "then he                60
                                                 Schema-
      wants to go to the                 50      inconsistent
      hospital" (not clear if lion       40      Schema-
      or zebra                                   consistent
                                         30
   – German 3 yr: "lion climbs
                                         20
      up to the window and falls
      down“                              10

• But: Few unrealistic or                0
  “fantasy” answers
                                            y




                                                        y




                                                                       y
                                             r




                                                         r




                                                                        r
                                          ua




                                                      ua




                                                                     ua
                                         an




                                                     an




                                                                    an
• German + Shuar similar:
                                      Sh




                                                  Sh




                                                                 Sh
                                        m




                                                    m




                                                                   m
                                     er




                                                 er




                                                                er
                                     G




                                                 G




                                                                G
  surprising on cultural view
                                     3 yrs           4 yrs          5 yrs
Summary of responses on predator-prey questions
          Consistent
100       No response

 90       Fantasy
          Folk-psychological
 80       Irrelevant
 70       Violation

 60
 50
 40
 30
 20
 10
  0
      German   Shuar           German   Shuar   German   Shuar

       3 yrs                     4 yrs           5 yrs
  Predator-prey schema: Summary
• Predator-prey schema is present at an early age across
  cultures
• Leads to realistic inferences about predator and prey
  behavior
• Similar in very different cultures, uncontaminated by
  cultural inputs like fairy tales and cartoons

• Other schemas?
                           Conceptual schemas
             Perceptual
 INPUTS      templates /
                             Predator-prey schema
              schemas

                                                              OUTPUTS
Perceptual                     Social Xch schema
  cues
                                         Etc.
                                                               Behavior
Knowledge                                                     predictions

                             Processor (“ToMM”)                Judgments
                                                               & Decisions


                           Human                John
               Scope
                             Dog
             restrictors                        Susan
                                  Lion                 Jim

                           Taxa                 Individuals
     Development of social exchange
               schema
         Barrett, Keller, Takezawa, Wichary


• Examined children’s judgments of violations of bilateral
  social contracts
• And predictions of reactions of different parties to
  violations
• German 1st and 4th graders
                                    Children’s judgments of contract
                                                violations

                                  100
Percent judging contract broken




                                                                               mutual
                                   80                                          compliance
                                                                               child
                                                                               violates
                                   60
                                                                               other
                                                                               violates
                                   40
                                                                               mutual non-
                                                                               compliance
                                   20


                                    0
                                        friend   sibling   neighbor   mother
Predicted reactions of victim of contract
                violation
                                            Anger in Simon when other violates


                             100
 Percent attributing anger




                              80

                              60
                                                                                 1st graders
                                                                                 4th graders
                              40

                              20

                               0
                                   friend       sibling    neighbor     mother
Predicted reactions of violator
                                            Guilt to Sim on when Sim on violates

                             100




                              80
Percent guilt attributions




                              60

                                                                                     1st grade
                                                                                     4th grade
                              40




                              20




                               0
                                   friend        sibling     neighbor       mother
 Social contract schema: Summary
• Even young children can identify contract violations
• Ability to predict other’s reactions in social exchange
  situations may be useful for moderating one’s own
  behavior

• Future research: what other schemas are there? When
  do they schemas develop? (e.g. mating?)
Switching the agency system on
            and off
             Agency detection
• Some things are agents, and some are not
• Agents require vigilance, and figuring out what
  they are trying to do
• Assuming everything is an agent entails costs
• Selects for discrimination between agents and
  non-agents
Agency detection activates appropriate
         inference systems

                      AGENT             NON-
                                       AGENT




           Activate                              Activate other
           agency                              object system (e.g.
           system                                  substance)
                             Different
                             patterns of
                             inference:

  Inferences licensed: can          Inferences licensed: can’t move, will not
  move, will react if touched,      react if touched, can be subdivided into
  can hurt you… etc                 pieces that retain properties, etc…
What about dead things?
  Death as the cessation of agency
                      Barrett and Behne


• Hypothesis:                       ALIVE        DEAD
                                     COW         STEAK
• Agency detection
  system contains a
  “remapping”
  routine
                         Activate                        Activate
                                        Deactivate
AGENT                   agency         agency          substance
  SUBSTANCE              system         system,          system
                                        activate
                                        substance
                                        system
                           Different inference patterns
    Cross-cultural test of cessation of
           agency hypothesis
• 3 to 5 year old German and Shuar children
• Sleep vs death: Animals and people
• Target questions:
   – Can it move?
   – If you touched it, could it move?
   – Could it hurt you?
   – If you made a noise, could it know you were there?
   – Could it be afraid?

• Sleep / death is a strong test
Patterns of inference for sleep vs death

                     Move?       If touched?       Hurt you?       Detect you?                   Be afraid?
                1
                                                                                                   GERMAN
               0.8
 Percent yes




               0.6                                                                                                            Sleep
               0.4                                                                                                            Death
               0.2
                0
                     3   4   5     3    4   5        3    4    5         3       4       5            3       4       5


                1
                                                                                                      SHUAR
               0.8
 Percent yes




               0.6                                                                                                             Sleep
               0.4                                                                                                             Death
               0.2
                0
                     3   4   5      3   4      5      3   4        5         3       4       5            3       4       5
                         Mean # correct responses by
                            population and age
                         10                        Human condition
                          9                        Animal condition

                          8
Number correct (of 10)




                          7
                          6
                          5
                          4
                          3
                          2
                          1
                          0
                              3    4   5    3      4         5

                              German       Shuar
   Cessation of agency: summary
• Agency inferences can be switched on and off
  for a particular object

• This aspect of agency detection present by age
  4 or earlier

• Same developmental trajectory across cultures:
  suggests core feature of agency system
Agency and social cognition

Is a norm violated if it is violated by mistake?
 Intentions and social contract violation

• Cosmides (1989: social contracts are agreements to
  exchange benefits
• Cheating = accepting benefit without paying cost

• But:
Suppose you agree to give your friend $1000 if he will give
  you his car next week. However, his car is stolen. Has
  he cheated you?
Perhaps intentions are an important part of social contracts.
           Social contract Wason
Social contract rule:

“If you give me your watch, then I will give you $10”

Watch         no watch      $10           $5

P             ~p            q             ~q

About 75% of people pick violation cards
    Manipulating intent, incentive, ability

•   Cover story manipulated so that potential violator either
    had:

1. Intent to violate, or violated by mistake
2. Incentive to violate, or no incentive
3. Ability to violate, or no ability (except at random)

•   How do the presence or absence of these factors affect
    subject’s vigilance for cheaters (card turning patterns)?
                 Operationalizing intent
Benefit / Intent / Ability:
You supervise four women who volunteered to help out at the local Board of
   Education. Your volunteers were supposed to follow certain rules for assigning
   students from various towns to the appropriate school district. Each volunteer is
   the mother of a teenager who is about to enter high school, and each processed
   her own child’s documents. You overheard that some of your volunteers
   intended to break the rules when it came to assigning their own children to a
   school. Here is the situation:
Although both communities are equally prosperous, the parents in Dover City have
   always cared about the quality of their schools, including Dover High, and have
   been willing to pay for it. In contrast, the parents in the neighboring town of
   Hanover have never wanted to spend the money, and have opposed any taxes to
   improve Hanover High. The Board of Education created this rule: “If a student
   is to be assigned to Dover High School, then that student must live in Dover
   City.”

A. Dover High School                B. Dover City
C. Hanover High School              D. town of Hanover
                    Without intent
• Benefit / Ability
• You supervise four women who volunteered to help out at the
  local Board of Education. Your volunteers were supposed to
  follow certain rules for assigning students from various towns
  to the appropriate school district. Each volunteer is the mother
  of a teenager who is about to enter high school, and each
  processed her own child’s documents. You know your
  volunteers are honest, but you suspect that they may have
  made some innocent mistakes: they may have broken the rules
  for assigning each child to a particular school...
  Operationalizing incentive, ability
• Incentive: parents sort their own students into schools, or
  only students of others

• Ability: students names are written on sheet, or students
  identified only by code numbers
~20%
Agency and social contracts: summary

• Vigilance for cheating affected ~ 20% for each factor
• Additive

• The difference between intentional and accidental
  violation of norms may be important in many other
  contexts as well: killing, politeness, fairness, etc..
Conclusion
            Summary of findings
• The agency system is not a single “ability,” but is
  comprised of many components
• Perceptual templates for identifying agents and specific
  intentions of agents
• Conceptual schemas for reasoning about intentions:
  provide the content for theory of mind
• Agency system can be turned on and off
• Agency system can influence social attribution and
  decision making processes
        Eventually, we will need a fully
          computational account…
                “Theory of mind”,
  INPUTS          “Belief / desire    OUTPUTS
                   reasoning”,
               “Intentional stance”

                                        Behavior
Perceptual
                                       predictions
  cues

Knowledge             ?                Judgments &
                                        Decisions



                 What’s in here?
       (Which might or might not look something like this.)
                             Conceptual schemas
               Perceptual
 INPUTS        templates /
                               Predator-prey schema
                schemas

                                                                OUTPUTS
Perceptual                       Social Xch schema
  cues
                                           Etc.
                                                                 Behavior
Knowledge                                                       predictions

                               Processor (“ToMM”)                Judgments
                                                                 & Decisions


                             Human                John
                Scope
                               Dog
              restrictors                         Susan
                                    Lion                 Jim

                             Taxa                 Individuals
   Understanding the agency system
   might have many implications for
    understanding social evolution.

  How important is the ability to understand
intent for the evolution of cooperation, norms,
                      etc?
The end

				
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