Figure 1

Policy sets and distributions used as illustrations. Policy sets used to illustrate the statistic are given in figures a – l, and distribution sets used are given in figures I – IV: see the Methods section for a full description of the policy and distribution sets. For both types of figure, the 20 × 20 squares represent the policy or distribution for focal individuals with 20 possible states (where a given individual is in state x) paired with co-players with 20 possible states (where a given individual is in state y).