Learn from External Memory, not just Weights: Large-Scale Retrieval for Reinforcement Learning
Modern RL architectures typically store the learned memory in the weights of the model. This way of storage is slow to learn as it not only takes several samples of backpropagation to update the weights correctly, but it can be unreliable as a change in some of the weights can affect earlier storage. This paper by DeepMind incorporates some form of utilizing external memory in the network via nearest neighbor search, and helps to learn faster from expert trajectories.
When evaluated on a 9x9 Go game, it performs better against the Pachi AI agent than simply doing more Monte Carlo Tree Search, and does better than without doing nearest neighbor retrieval. There is some use of an external memory for learning, and in this work they empirically demonstrated its performance in learning and inferring good trajectories from examples.
I was inspired by this work, and sought to improve it by making the memory learnable and goal-directed, and this will be described in my future work titled "Learning, Fast and Slow"
Paper Link: https://arxiv.org/abs/2206.05314
Slides: https://github.com/tanchongmin/TensorFlow-Implementations/tree/main/Paper_Reviews
Related videos:
Learning, Fast and Slow: https://www.youtube.com/watch?v=Hr9zW7Usb7I
A New Framework of Memory for Learning: https://www.youtube.com/watch?v=q9uMEAcB3lM
Reinforcement Learning, Fast and Slow: https://www.youtube.com/watch?v=M10f3ihj3cE
0:00 Introduction
4:57 Neural Networks vs External Memory
17:52 Memory to augment observations
21:31 Scalable Memory Retrieval
37:17 Robust Way of Leveraging Data
40:43 Memory as abstraction
43:23 Overall Model
48:38 Experiment Setup
51:53 Results
1:15:00 Neighbour Regularisation
1:20:57 Discussion
1:32:22 My own follow-up work: Learning, Fast and Slow
1:35:54 Motivation and Final words
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AI and ML enthusiast. Likes to think about the essences behind breakthroughs of AI and explain it in a simple and relatable way. Also, I am an avid game creator.
Discord: https://discord.gg/fXCZCPYs
LinkedIn: https://www.linkedin.com/in/chong-min-tan-94652288/
Online AI blog: https://delvingintotech.wordpress.com/.
Twitter: https://twitter.com/johntanchongmin
Try out my games here: https://simmer.io/@chongmin