I'm using RL to train a Network on the game Connect4. It learns quickly that 4 connected pieces is good. It gets a reward of 1 for this. A zero is rewarded for all other moves.
It takes quite a time until the AI tries to stop the opponent from winning.
Is there a way this could be further reinforced?
I thought about giving a negative reward for the move played before the winning move. Thinking about this, I came to the conclusion that this is a bad idea. There'll be always a looser (except for ties), therefore there always be a last move from the losing player. This one hasn't to be a bad one. Mistakes could have been made much earlier.
Is there a way to improve this awareness of opponents? Or does it just have to train more?
I'm not perfectly sure if the rewards will propagate back in a way that encourages this behavior with my setup.