Groups and War Lab

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https://hdl.handle.net/1794/19452

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Browsing Groups and War Lab by Author "Orbell, John"

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    Ancestral War and the Evolutionary Origins of "Heroism"
    (University of Chicago Press, 2007-11) Smirnov, Oleg; Arrow, Holly; Kennett, Douglas J.; Orbell, John
    Primatological and archeological evidence along with anthropological accounts of hunter-gatherer societies indicate that lethal between-group violence may have been sufficiently frequent during our ancestral past to have shaped our evolved behavioral repertoire. Two simulations explore the possibility that heroism (risking one’s life fighting for the group) evolved as a specialized form of altruism in response to war.We show that war selects strongly for heroism but only weakly for a domain-general altruistic propensity that promotes both heroism and other privately costly, group-benefiting behaviors. A complementary analytical model shows that domain-specific heroism should evolve more readily when groups are small and mortality in defeated groups is high, features that are plausibly characteristic of our collective ancestral past.
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    "Social Poker": A Laboratory test of Predictions form Club Theory
    (SAGE Publications, 2004) Crosson, Scott, 1970-; Orbell, John; Arrow, Holly
    The theory of clubs addresses the gap between purely private and purely public goods, being concerned with how groups (‘clubs’) form to provide themselves with goods that are available to their membership, but from which others (non-members) can be excluded. Despite 35 years of formal development, there have been virtually no laboratory studies of club formation. We develop the ‘social poker’ laboratory paradigm toward filling this gap, and test the predictions from club theory that populations will partition into a privately and socially optimal set of clubs. The experiment included three conditions: (1) ‘Single shot’ with one trial of club formation; (2) ‘iterated’ with a sequence of four trials; and (3) ‘iterated dollar-guarantee’, with four trials in which participants who were not included in clubs still earned a small amount of money. In all conditions, clubs were frequently larger than was privately or collectively optimal; in the second condition, clubs were increasingly likely to include unnecessary members across trials. After clubs formed, members had the opportunity to ‘overclaim’ – to take more than their agreed-upon share of the club good. Although the incidence of overclaiming was low, it was more common in larger clubs, further reducing the collective earnings of participants.