How Implicit Communication Emerges during Conversation Game

In this research, we used an evolutionary computation to investigate a linguistic phenomenon, implicit communication. Implicit communication is a phenomenon related to language evolution. This phenomenon performs as an ability to "read" an opponent's real intention from their superficial message [1]. Implicit communication generally means that talking has an implicit meaning which is shared by people in a subgroup [3]. This implicit communication is useful for achieving coordination in a subgroup, when the competitor is in a group. This type of implicit communication is expected to emerge and be changed during communication. For example, people in Japan's old city Kyoto use the phrase "recommend of simple dinner" as "recommendation to go home." This kind of inverted meaning of implicit communication shows who is an outsider of the group. Implicit communication is expected to emerge according to the evolution of a language. For example, slang is a kind of implicit communication, that is generated in a subgroup of a community for communicating each other. Implicit communication is also a smart strategy on conversation games. Lee et al. suggested that game players with implicit communication show better communication than players with a fixed mindset [4]. In this research, we study implicit communication with a conversation game, werewolf. Werewolf is a reinvention of a multi-player conversation game, Mafia [10][11]. In the werewolf game, players are distributed into two subgroups with hidden identity. One subgroup includes villagers. Villagers' purpose is to find out their enemies, werewolves in