Considering the lack of information of other agents, relative aggressiveness becomes important for decision making and interaction. Assuming the two players are player one and player two, from player one's perspective, the aggressiveness of player two can be classified into three types: equally aggressive, less aggressive, and more aggressive. The probability distribution of these three types \(p_j(\sum p_j = 1 (j = 1,2,3))\) subjects to a multinomial distribution. Different types of the player two have different forms of utility functions, which are summarized in Table \ref{t2}.