Monte Carlo#

The Monte Carlo approach for reinforcement learning is a model-free technique for solving Markov Decision Processes (MDPs). The approach is based on the idea of estimating the expected reward of an action through simulation, rather than explicitly modeling the transition probabilities and rewards of an MDP.

In the Monte Carlo approach, an agent interacts with the environment and records its experiences, including the states, actions, and rewards it receives. The agent uses these experiences to update its estimate of the expected reward for each action in each state. This estimate is based on the average of the observed rewards that resulted from taking that action in that state.

The Monte Carlo approach requires sufficient exploration of the environment in order to accumulate enough experiences to estimate the expected rewards accurately. Once enough data has been collected, the agent can use the estimated rewards to make decisions that maximize its expected reward over time.

One advantage of the Monte Carlo approach is that it is model-free, so it does not require explicit knowledge of the transition probabilities or reward function of the environment. This makes it well-suited for complex or poorly understood environments. Additionally, the Monte Carlo approach can handle non-stationary environments, where the reward function and transition probabilities change over time.

However, the Monte Carlo approach can also suffer from slow convergence, especially in sparse reward environments where the agent may take many steps between receiving rewards. Additionally, the approach requires a large amount of data to accurately estimate the expected rewards, which can be computationally expensive and time-consuming.