ATLA-SA¶
ATLA with state-adversarial regularisation and a recurrent policy
OnlineLearner-centricBase · PPOClaims · observation shift
ATLA plus a state-adversarial KL regulariser and a 100-step recurrent policy.
Features¶
| Feature | Value |
|---|---|
| Group | Robust Online Algorithms |
| Setting | Online |
| Family | Learner-centric |
| Base algorithm | PPO (LSTM policy) |
| Claimed robustness | Observation shift |
| Shifted-env rollout | No |
| Adversarial network | Yes |
| Learned model | No |
| Training budget | About 5M environment steps (2441 iterations of 2048 steps) |
| Original paper | Zhang et al. Robust Reinforcement Learning on State Observations with Learned Optimal Adversary. ICLR, 2021. |
Mechanism¶
ATLA-SA adds the SA-PPO regulariser to ATLA: a KL penalty between the policy at a state and at the worst-case neighbour found by stochastic gradient Langevin dynamics. It also uses a recurrent (LSTM) policy with a 100-step history, so that the agent can infer a persistent perturbation from context.
Implementation notes.
- Gradient-based observation attacks are not applicable to this method: a recurrent policy has no differentiable feed-forward actor to attack.
Run the method¶
python baselines/train.py \
-c robustrllib/configs/experiment/atla_sa_hopper.yaml --seed 0
python baselines/evaluate.py --run runs/atla_sa_hopper/seed0
| File | Path |
|---|---|
| Implementation | baselines/atla |
| Algorithm card | robustrllib/configs/algorithm/atla_sa.yaml |
| Experiment file | robustrllib/configs/experiment/atla_sa_hopper.yaml |
Training is on the nominal task. The configuration files are explained in Train an algorithm, and the evaluation of the frozen checkpoint in Evaluation Protocol.
Robust performance¶
Normalized score of the frozen checkpoint. Q1 to Q4 are the severity quartiles of each shift factor's scales, ordered by displacement from the nominal setting, and All covers every shifted condition. The last row averages the tasks.
| Task | Nominal | Q1 | Q2 | Q3 | Q4 | All |
|---|---|---|---|---|---|---|
| CarRacing | 80.7 | 73.6 | 79.3 | 58.5 | 51.9 | 64.8 |
| FetchReach | 96.3 | 93.2 | 85.7 | 77.4 | 78.0 | 83.6 |
| HalfCheetah | 44.0 | 41.7 | 33.6 | 25.6 | 19.3 | 30.0 |
| Hopper | 102.2 | 81.9 | 66.8 | 50.5 | 32.4 | 57.9 |
| PointMaze | 78.7 | 82.0 | 77.7 | 83.2 | 52.1 | 73.7 |
| Walker2d | 63.6 | 60.4 | 47.2 | 42.7 | 39.3 | 47.4 |
| Average | 77.6 | 72.1 | 65.0 | 56.3 | 45.5 | 59.6 |
References¶
- Zhang et al. Robust Reinforcement Learning on State Observations with Learned Optimal Adversary. ICLR, 2021.
- Zhang et al. Robust Deep Reinforcement Learning against Adversarial Perturbations on State Observations. NeurIPS, 2020.