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Equation 13 · Part 1 · Why We Punish Strangers: The Evolution of Human Cooperation

Symbol w_p

wp=k(1−x−y)w_p = k(1 - x - y)
wpw_p

What this part means

wpw_p is part of the quantity the equation computes from the expression on the right.

Its job in the formula

wpw_p is part of the quantity the equation computes from the expression on the right.

The passage around this formula

The first is cultural group selection, formalized by Robert Boyd, Herbert Gintis, Samuel Bowles and Peter Richerson. Their starting problem is that punishing free-riders is itself a public good — everyone in a group benefits if free-riders are deterred, but only the punisher pays the cost of deterring them, so a population of willing punishers should in principle be invaded by cooperators who never bother to punish, a “second-order” free-rider problem sitting on top of the first [ 9 ] . Their proposed way out rests on an asymmetry between the two roles. A plain cooperator who does not punish pays a fixed cost, call it c , simply by cooperating, regardless of how many other group members…

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Sources cited in the surrounding passage

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