Informatical Analysis of Go, Part 1: Evolutionary Changes of Board Size

This paper explores the nature of the Go game. Go has been played on different size of the board in its long history where it was born in 2356 BC and played on 9×9 board, and later played on 13×13, 15×15, 17×17, 19×19, and 21×21 board. Self-play experiments using an open-source implementation of AlphaZero, namely LeelaZero, as the artificial intelligence (AI) player, are conducted for data collection, whereas game refinement (GR) measures had been employed for the assessment. An informational analysis indicates that Go game have been searching not only for a harmonic balance between deterministic and stochastic aspects found in the similar board games (Chess and Mahjong) but also the expected fairness when playing Go. Three aspects of the game have been analyzed: the perspective of game designer (using the GR measure), the perspective of Go evolution relative to Chess and Mahjong evolutionary histories, and other perspectives that closely related to the cultural and strategic development of Go game. Based on such aspects, the impact of komi values and the reasons for 19×19 board size to the contemporary Go popularity had been identified.