. 2016 May 10;6:25676. doi: 10.1038/srep25676

Table 1. Four different strategy spaces considered in this work. Each parameter p_ij denotes the focal player’s probability to cooperate in the next round, given that the player’s previous action was i and that the co-player's action was j.

	Reactive strategies	Memory-1 strategies
Deterministic strategies	Deterministic reactive strategies, p_CC = p_DC, p_CD = p_DD p_ij ∈ {0, 1}	Deterministic memory-1 strategies, p_ij ∈ {0, 1}
Stochastic strategies	Stochastic reactive strategies, p_CC = p_DC, p_CD = p_DD p_ij ∈ [0, 1]	Stochastic memory-1 strategies, p_ij ∈ [0, 1]

Table 1. Four different strategy spaces considered in this work. Each parameter pij denotes the focal player’s probability to cooperate in the next round, given that the player’s previous action was i and that the co-player's action was j.