Reviewing reinforcement learning concepts

In a way, RL can be defined as learning from mistakes. Instead of getting the feedback for every data instance, as is the case with supervised learning, the feedback is received after a sequence of actions. The following diagram shows the high-level schematic of an RL system:

Figure 9.1 – Reinforcement learning schematic

In an RL setting, we usually have an agent, which does the learning. The agent learns to make decisions and take actions according to these decisions. The agent operates within a provided environment. This environment can be thought of as a confined world where the agent lives, takes actions, and learns from its actions. An action here is simply the implementation of the decision the agent makes based on what it has learned.

We mentioned earlier that unlike supervised learning, RL does not have an output for each and every input; that is, the agent does not necessarily receive a feedback...