The prescriptions of the leading eight.

The top row (X, Y) indicates the reputations of the donor and the recipient, respectively. For instance, (G, B) means the case where a good (G) donor meets a bad (B) recipient. The rules P, R1(C), R1(D) indicate the prescribed action, the assessment when cooperation (C) is observed, and the assessment when defection (D) is observed, respectively. The entry 1 means C or G, whereas 0 means D or B. The entries that are different from each other are highlighted in bold text. In the bottom row, the common prescriptions are shown, where * means that the entry is arbitrary and † means that the entry is determined according to R1(B, B, C) and R1(B, B, D). These norms are CESS for b/c > 1 in the rare error limit.