Contents

- 1 Is Q learning value-based or policy based?
- 2 What is model based RL?
- 3 Is AlphaZero model based?
- 4 Why is Q learning off policy?
- 5 What is model based model RL free?
- 6 What’s the difference between model-based and Q-learning?
- 7 When to use DQN for approximated Q-learning?
- 8 What’s the difference between Double Q and Double Q-learning?
- 9 How is Q-learning different from other learning algorithms?

## Is Q learning value-based or policy based?

Q learning is a value-based off-policy temporal difference(TD) reinforcement learning. Off-policy means an agent follows a behaviour policy for choosing the action to reach the next state s_t+1 from state s_t.

## What is model based RL?

Model-based Reinforcement Learning refers to learning optimal behavior indirectly by learning a model of the environment by taking actions and observing the outcomes that include the next state and the immediate reward.

## Is AlphaZero model based?

Model-Free vs Model-Based RL Agents can then distill the results from planning ahead into a learned policy. A particularly famous example of this approach is AlphaZero. Algorithms which use a model are called model-based methods, and those that don’t are called model-free.

## Why is Q learning off policy?

Q-learning is called off-policy because the updated policy is different from the behavior policy, so Q-Learning is off-policy. In other words, it estimates the reward for future actions and appends a value to the new state without actually following any greedy policy.

## What is model based model RL free?

Model-Based RL According to OpenAI – Kinds of RL Algorithms, algorithms which use a model of the environment, i.e. a function which predicts state transitions and rewards, are called model-based methods, and those that don’t are called model-free.

## What’s the difference between model-based and Q-learning?

Whereas, a model-based algorithm is an algorithm that uses the transition function (and the reward function) in order to estimate the optimal policy. Q-learning is a model-free reinforcement learning algorithm. Q-learning is a values-based learning algorithm.

## When to use DQN for approximated Q-learning?

Using DQN for approximated Q-learning is called Deep Q-Learning. In a model-based RL environment, the policy is based on the use of a machine learning model. To better understand RL Environments/Systems, what defines the system is the policy network.

## What’s the difference between Double Q and Double Q-learning?

Double Q-learning. A variant called Double Q-learning was proposed to correct this. Double Q-learning is an off-policy reinforcement learning algorithm, where a different policy is used for value evaluation than what is used to select the next action.

## How is Q-learning different from other learning algorithms?

Q-learning is a values-based learning algorithm. Value based algorithms updates the value function based on an equation (particularly Bellman equation). Whereas the other type, policy-based estimates the value function with a greedy policy obtained from the last policy improvement. Q-learning is an off-policy learner.