enhanced meta reinforcement learning
Supplementary material: Enhanced Meta Reinforcement Learning using Demonstrations in Sparse Reward Environments
We will use the well known Performance Difference Lemma [16] in our analysis. We can obtain a performance difference lemma for the meta-policies as follows. Here, we get (a)is from Assumption 3.1 from which we have P In this section, we describe all the simulation and real-world environments in detail. B.1 Simulation Environments Point 2DNavigation: Point 2DNavigation [9] is a 2 dimensional goal reaching environment with S R2, A R2, and the following dynamics, xt+1 = xt +dxt, yt+1 = xt +dyt, such that dx2t +dy2t 0.12 Where xt and yt are the x and y location of the agent, dxt and dyt are the actions taken which correspond to the displacement in the x and y direction respectively, all taken at time step t. The goals are located on a semi circle of radius 2, and the episode terminates when the agent reaches the goal or spends more than 100time steps in the environment.
Enhanced Meta Reinforcement Learning via Demonstrations in Sparse Reward Environments
Meta reinforcement learning (Meta-RL) is an approach wherein the experience gained from solving a variety of tasks is distilled into a meta-policy. The meta-policy, when adapted over only a small (or just a single) number of steps, is able to perform near-optimally on a new, related task. However, a major challenge to adopting this approach to solve real-world problems is that they are often associated with sparse reward functions that only indicate whether a task is completed partially or fully. We consider the situation where some data, possibly generated by a sub-optimal agent, is available for each task. We then develop a class of algorithms entitled Enhanced Meta-RL via Demonstrations (EMRLD) that exploit this information---even if sub-optimal---to obtain guidance during training. We show how EMRLD jointly utilizes RL and supervised learning over the offline data to generate a meta-policy that demonstrates monotone performance improvements. We also develop a warm started variant called EMRLD-WS that is particularly efficient for sub-optimal demonstration data. Finally, we show that our EMRLD algorithms significantly outperform existing approaches in a variety of sparse reward environments, including that of a mobile robot.
Enhanced Meta Reinforcement Learning via Demonstrations in Sparse Reward Environments
Meta reinforcement learning (Meta-RL) is an approach wherein the experience gained from solving a variety of tasks is distilled into a meta-policy. The meta-policy, when adapted over only a small (or just a single) number of steps, is able to perform near-optimally on a new, related task. However, a major challenge to adopting this approach to solve real-world problems is that they are often associated with sparse reward functions that only indicate whether a task is completed partially or fully. We consider the situation where some data, possibly generated by a sub-optimal agent, is available for each task. We then develop a class of algorithms entitled Enhanced Meta-RL via Demonstrations (EMRLD) that exploit this information---even if sub-optimal---to obtain guidance during training.