Paper Overview
Field: Machine Learning Authors: Chainesh Gautam, Raghuram Bharadwaj Diddigi, Chandramouli Kamanchi, Pankaj Dayama, Sumanta Mukherjee, Kameshwaran Sampath arXiv: 2609.31586
Summary
Decision Transformer performance degrades on long rollouts because the conditioning context drifts out of the training distribution. The authors show that this drift is visible through the model's own next state prediction error, which rises during rollout and stays elevated, giving a direct signal of when context has become unreliable.
They introduce Trust Guided Decision Transformer (TGDT), which selects context before applying value guidance:
- At each step, TGDT evaluates several recent context suffixes using rolling next state prediction error.
- Thresholds are calibrated against held-out offline data via split conformal prediction.
- Only suffixes whose error stays within the calibrated threshold are kept.
- A frozen critic then chooses the highest-value action among the trusted suffixes.
- The original Decision Transformer
- Reset-based context control
- Value-only context selection
This reverses the order of value-only elastic selection, which may pick an action generated from a context the model itself has already flagged as unreliable.
Results
Experiments on D4RL navigation and locomotion tasks show that state prediction, critic guidance, and hard context resets each address only part of the problem. TGDT reduces persistent high-error runs and achieves returns exceeding:
Original Abstract (excerpt)
> Decision Transformer performance degrades on long rollouts because the conditioning context drifts out of the training distribution. We show that this drift is visible through the model's own next state prediction error, which rises during rollout and stays elevated, giving a direct signal of when context has become unreliable. We introduce Trust Guided Decision Transformer (TGDT), which selects context before applying value guidance...
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*Auto-collected on 2026-09-29. Source: arXiv:2609.31586*