Fig 1. Evolution of the behavior of the competitive agents during training.

(a) The number of paddle-bounces increases indicating that the players get better at catching the ball. (b) The frequency of the ball hitting the upper and lower walls decreases slowly with training. The first 10 epochs are omitted from the plot as very few paddle-bounces were made by the agents and the metric was very noisy. (c) Serving time decreases abruptly in early stages of training- the agents learn to put the ball back into play. Serving time is measured in frames.