Generative adversarial imitation learning
Generative Adversarial Imitation Learning (GAIL) is another very popular IRL algorithm. As the name suggests, it is based on Generative Adversarial Networks (GANs), which we learned about in Chapter 7, Deep Learning Foundations. To understand how GAIL works, we should first recap how GANs work.
In a GAN, we have two networks: one is the generator and the other is the discriminator. The role of the generator is to generate new data points by learning the distribution of the input dataset. The role of the discriminator is to classify whether a given data point is generated by the generator (learned distribution) or whether it is from the real data distribution.
Minimizing the loss function of a GAN implies minimizing the Jensen Shannon (JS) divergence between the real data distribution and the fake data distribution (learned distribution). The JS divergence is used to measure how two probability distributions differ from each other...