1. Can race be erased? Coalitional computation and social categorization
Robert Kurzban, John Tooby, and Leda Cosmides
Presentation by:
Anne-Lise Nilsen and Adam Szymankiewicz

2. Intro
Background:
Intergroup conflict depends on categorizing the world into US vs. THEM
→ Predisposes humans to discriminate in favor of ingroup and against outgroup
Because of this it is thought that when you meet someone new it activates 3 “primitive” or “primary dimensions”
Race, Sex and Age

3. Intro Evolutionary Psychology perspective: According to the EEA…
This is not true regarding race… hunter and gatherers would never meet other “races” therefore could not have evolved the cognitive mechanisms that would automate this info.

4. Intro
Hypothesis: The (apparently) automatic and mandatory encoding of race is instead a byproduct of adaptations that evolved for an alternative function that was a regular part of the lives of our foraging ancestors: detecting coalitions and alliances.

5. Intro Coalitions and Alliances
Evolutionarily: Within the bands of hunter and gatherers, there were coalitions and alliances. This is also found within other non-human primates.
Neuro-cognitive mechanisms which tracked shifting alliances would have been beneficial to successfully negotiate their social world, therefore could be selected for.

6. Intro Neurocognitive mechanism should be sensitive to:
patterns of coordinated action, cooperation and competition
cues that predict- either purposefully or incidentally- each individuals political allegiances
*“Because this circuitry detects correspondence between allegiances and appearance, stable dimensions of shared appearance- which may be otherwise, meaningless- emerge in the cognitive system as markers of social categories.”

7. Intro
Any readily observable feature- however arbitrary- can acquire social significance and cognitive efficacy when it valididates cues patterns of alliance.
example: dress, dialect, manner, gait, family resemblance, ethnic & coalitional badges
But what about sex, which ancestorially is fixed?

8. Predictions
1. Race will not be encoded across all social contexts when manipulated coalitional variables.
2. Shared visual appearance is not necessary for coalition encoding. But it can reinforce and stabilize a coalitional categorization.
3. Arbitrary cues other than race can be endowed with the same properties that race has previously exhibited by linking to coalitional membership.
4. Race encoding will be diminished when:
*Race is no longer a valid cue
*Alternative cues are present that do reliably predict
5. Sex will be encoded stronger than race even when irrelevant
6. Encoding of sex will not diminish coalition encoding

9. Methods
Subjects
- Undergraduates at the University of California, Santa Barbara
- Men to Women: ~50:50
- primarily Euro-American and Asian American
E1: 55 participants
E2: 52 participants
E3: 55 participants
E4: 57 participants
E5: 51 participants
E6: 52 participants

10. Methods Memory confusion protocol
1) subjects are asked to form impressions of individuals whom they will see engaged in a conversation
2) See a sequence of sentences paired with a photo of individual who said it
24 sentences, 8.5 sec each
Each sentence paired with a photo of one man
3) Surprise recall task - sentences in random order, attributing them to the individual that said it
Misattributions reveal encoding - subjects more readily confuse individuals whom they have categorized as members of the same category than those whom they have categorized as members of different categories.

11. Methods Rival coalitions constructed such that race was uncorrelated
with coalition membership:
- the rival four-person coalitions
were each composed of two
European-American and two
African-American men

12. Methods This design allowed to:
E1: replicate the basic phenomenon of racial encoding
E2: see whether the tendency to encode race could in fact be reduced by an introduction of a visually accessible cue to a non-racial coalition division
E3:replicate the basic phenomenon of encoding via sex
E4: see whether the tendency to encode sex could be reduced by an introduction of a visual cue
E5&6: Replicate the E1 and E2 studies for validity

13. Methods
If the human brains contains neurocomputational machinery for tracking coalitional alliances , then constructing a new social environment in which coalition is uncorrelated with race should weaken the preexisting weight given to race as a cue to a coalition within that context.
If though the prior claims are correct - if race is a prior dimension of person representation, then encoding this new social environment should make no difference.

14. Methods Experiment 1 - no visual cues to coalition membership
- all male, same shirts, mixed races
- coalition allegiance inferred only from content and sequence of their utterances

15. Methods
Experiment 2
- same as E1 only difference: shared appearance to the coalition through verbal allegiance cues (same color of shirts of members of the same coalition)
- if prediction 3 is true: coalition will be spontaneously encoded in exp 2 just as strongly - or more so - than race is.

16. Methods
Experiment 3:
Run in an identical manner as experiment 1 except sex was used instead of race
No visual cues of coalition alliance

17. Methods
Experiment 4:
Run in an identical manner as experiment 2 except sex was used instead of race
Coalition members wore the same color shirt

18. Methods
Experiments 5 & 6
exact replicates of experiment 1 and 2 except for different individuals in the pictures.

19. Results
Experiment 1
Subjects encoded a new dimension: coalition membership
More within than between coalition errors
Effect of Race twice as large as the effect of coalition
Effect size of coalition = 0.31
Effect size of race = 0.67

20. Results
Experiment 2
Effect of Coalition marked by cues of shared appearances
Effect size of coalition = 0.79 (
Effect size of race = 0.49
Shows that a new and arbitrary coalition can be encoded just as strongly as race is

21. Results Experiment 2 Two questions:
when does race ceased to be a predictor of coalitional allegiance within a given social context?
Does coalition acquire the robust properties race had & does race lose the strength it once had in a situation when a coalition membership is marked by cues of shared appearances?

22. Results Experiments 3 & 4 When cues to coalition had to be inferred:
effect size for coalition= 0.35 (p=0.0045)
*comparable to experiment 1
When cues were amplified:
effect size for coalition= 0.81 (p= 9.6 x 10^-15)
*comparable to experiment 2

23. Results: Experiments 3 & 4
But… the extent at which subject categorized targets, sex was very high in experiment 3 and 4
*Experiment 3: effect size= 0.91 (p=3.2x10^-22)
*Experiment 4: effect size= 0.84 (p=1.1x10^-19)
Sex was always encoded more strongly than coalition
Effect sizes for sex were significantly larger than race in analogous conditions
sex (ex. 3): 0.91 vs race (ex. 1): 0.67 (p= )
sex (ex. 4): 0.84 vs race (ex. 2): 0.49 (p= )
t tests give complementary results

24. Results: Experiment 3 & 4
Main take away:
Categorizing based on sex stays high even when coalitional cues are amplified, but race effects disappear.

25. Results: Experiment 5 & 6
Replicated results of experiment 1 and 2 when cues to coalitional alliance were verbal only. (significant race effect)
But when cues to coalitional alliance were augmented visually, the size of the race effect dropped substantially from 0.57 to 0.15 (p=0.0073)
“In this condition it would appear that the extent to which subject encoded targets by their race was not merely diminished, it was erased.”

26. Figure 1

27. Figure 2.

28. Conclusions and Discussion
- Ethnicity (Race) is an ecologically valid prediction of people’s social alliances
- Racial encoding sensitive to coalition manipulation
- < 4 min exposure to an environmental coalition (shirt color) decreased the effect of race

29. Limitations - Diversity of participants didn’t match the
diversity within the picture

30. Questions - What does our elephant say about that?
-Where would mixed race
individuals fall under
categorizations?