What is Transfer reinforcement learning

The Power of Transfer Reinforcement Learning in AI

Reinforcement learning has been a popular field in AI research, with its ability to teach an agent to make decisions by trial and error. However, one limitation of reinforcement learning is the need for a large amount of data to achieve optimal performance. To overcome this issue, researchers have developed transfer reinforcement learning, which utilizes the knowledge gained from solving one task to inform the learning process of another task.

What is Transfer Learning?

Transfer learning is a method of training machine learning models where knowledge gained during training from one task is transferred to a different but related task. This technique is particularly useful in achieving better performance with smaller datasets, thus reducing the amount of data required for training.

What is Reinforcement Learning (RL)?

Reinforcement Learning is an AI technique that teaches an agent to make decisions by trial and error. The agent learns to maximize rewards and minimize penalties through repeated interactions with the environment. The ultimate goal is to find an optimal policy that leads to maximum rewards. The agent learns through exploration and exploitation: it explores different strategies to find the best one and exploits the best strategy once it's determined.

What is Transfer Reinforcement Learning (TRL)?

Transfer Reinforcement Learning (TRL) is a type of transfer learning in which knowledge gained from one task is applied to another related task in the reinforcement learning framework. With TRL, an agent learns to overcome a new task with the help of knowledge stored from prior similar tasks that use the same reward function and state space.

Benefits of Transfer Reinforcement Learning
  • Improved Learning Efficiency: In TRL, prior knowledge can be used to guide the learning algorithm to find a good solution quickly, thereby reducing the amount of data required for training.
  • Reduced Data Complexity: TRL eliminates the need for significant amounts of data, thus reducing time and computation for training.
  • Leverages Existing Knowledge: Existing solutions from identical or closely related tasks can be used to solve new problems effectively.
  • Robustness: The robustness of the performance of the agent increases because of its ability to handle variations of the given task.
Techniques of Transfer Reinforcement Learning

There are several techniques to implement Transfer Reinforcement Learning:

Policy Transfer

Policy transfer involves reusing previously learned policies or strategies to solve a new task. In this method, the agent utilizes prior knowledge acquired from solving a similar game to learn the new game. The strategy learned from the old game is applied with minimal or no modifications to solve the new game, thus reducing the exploration time required to learn the new game.

Value Function Transfer

Value function transfer is another TRL technique that involves using the value functions learned from an old game to solve a new game. The value function is a mapping from states to the expected long-term rewards. It is used to determine the optimal policy that leads to maximum reward. By transferring the value function learned from the old game, a reinforcement learning agent can learn the new game faster.

Each Task a Committee (ETAC)

Each task a committee (ETAC) is a TRL technique that involves training multiple agents to solve different but related tasks. Instead of transferring the knowledge learned from previous tasks to a new task, ETAC's approach is to have different agents solve different tasks and use their decisions as inputs to a committee that selects the best approach for the new task. The committee then outputs the optimal policy for the new task.

Applications of Transfer Reinforcement Learning

TRL is gaining popularity in various applications. Here are some applications of TRL:


TRL is used in robotics to enable robots to learn new tasks faster by building on knowledge gained from previous tasks. Robots can learn new movements or manipulations by leveraging prior knowledge to reduce exploration time and improve performance.


TRL helps in training intelligent agents to play new games using knowledge from previous games. For example, TRL can be used to teach an agent to solve a new puzzle game based on previous experiences of solving similar puzzles.

Autonomous Driving

TRL can help in developing autonomous driving agents. Prior knowledge of driving in various environments can be leveraged to improve their behavior in new driving scenarios.


TRL is a promising and powerful technique that has the potential to revolutionize the field of reinforcement learning. It eliminates the need for significant amounts of data for training, enhances performance on related tasks, and encourages transfer of knowledge. The technology could help to decrease development time and reduce computational costs, making it a popular choice across a variety of applications.