Building Machine Learning Systems with Python - Third Edition

Policy and value network

We can start with solving Go. Go is a simple game that is thousands of years old. It's a two player game with full information, meaning that two players face each other and there is no hidden knowledge; everything is contained on the board (contrary to, say, card games like poker). At each turn, the player places one of their stones (either white for the first player or black for the second) on the board, possibly changing the color of other stones in the process, and the games ends with whoever has the most stones of their color.

The issue is that the board is quite big, 19 x 19 squares, meaning that at the beginning you have a very big set of possible options. Which one leads to winning the game?

For chess, this ...