Curriculum learning
When we learn a new skill, we start with basics. Bouncing and dribbling are the first steps while learning basketball. Doing alley-oops is not something to try to teach in the first lesson. One needs to gradually proceed to advanced lessons, after feeling comfortable with the earlier ones. This idea of following a curriculum, from basics to advanced levels, is the basis of the whole education system. The question is whether machine learning models can benefit from the same approach. It turns out that they can!
In the context of RL, when we create a curriculum, we similarly start with "easy" environment configurations for the agent. This way the agent can get an idea about what success means early on, rather than spending a lot of time by blindly exploring the environment with the hope of stumbling upon success. We then gradually increase the difficulty if we observe the agent is exceeding a certain reward threshold. Each of these difficulty levels are...