Writing study: Overcoming Joint Intractability with Lossless Hierarchical Speculative Decoding
← ICLR 2026 oral writing corpus
Yuxuan Zhou, Fei Huang, Heng Li, Fengyi Wu, Tianyu Wang, jianwei zhang, Junyang Lin, Zhi-Qi Cheng · Official ICLR 2026 oral record
Figure, table and section ledger
Editorial contribution type: Inference, algorithms & systems efficiency (primary) · Theory & formal foundations.
Layout extraction, not a required paper template. Counts are distinct caption labels; a multi-panel figure counts once. Section spans are estimated from heading positions, including floats and whitespace. Method and limitations.
- Canonical PDF
- 34 physical pages
- Before references / appendix
- ≈ 10.21 page-equivalents
- Main figures / tables
- 2 / 4
- Attached appendix figures / tables
- 1 / 4
- Attached appendix span
- ≈ 21.4 page-equivalents
Section-by-section lengths and source pages
The title/abstract/front matter precede the first numbered heading. A span ends at the next detected top-level heading, not at the last sentence; end-page whitespace is included. References and statements are listed separately. These are not measurements of text-only or artwork area.
| Top-level heading | Starts on PDF page | Estimated span | Share of entire PDF |
|---|---|---|---|
| 1 INTRODUCTION | 1 | ≈ 1.12 pp. | 3.29% |
| 2 RELATED WORK | 2 | ≈ 0.52 pp. | 1.53% |
| 3 REVISITING TOKENWISE SPECULATIVE DECODING | 3 | ≈ 0.42 pp. | 1.24% |
| 4 THEORETICAL FOUNDATIONS OF HIERARCHICAL SPECULATIVE DECODING | 3 | ≈ 2.05 pp. | 6.03% |
| 5 HIERARCHICAL SPECULATIVE DECODING | 5 | ≈ 3.5 pp. | 10.29% |
| 6 EXPERIMENTS | 9 | ≈ 1.67 pp. | 4.91% |
| 7 CONCLUSION | 10 | ≈ 0.28 pp. | 0.82% |
| ACKNOWLEDGMENTS | 11 | ≈ 0.11 pp. | 0.32% |
| REFERENCES | 11 | ≈ 2.39 pp. | 7.03% |
| APPENDIX | 13 | ≈ 0.04 pp. | 0.12% |
| A THEORETICAL FOUNDATION | 13 | ≈ 2 pp. | 5.88% |
| B LOSSLESS OF NAIVE HIERARCHICAL SPECULATIVE DECODING | 15 | ≈ 3.47 pp. | 10.21% |
| C LOSSLESS OF HIERARCHICAL SPECULATIVE DECODING | 19 | ≈ 4.38 pp. | 12.88% |
| D EXPECTED NUMBER OF ACCEPTED TOKENS | 23 | ≈ 4.96 pp. | 14.59% |
| E EXTENDED EXPERIMENTS | 28 | ≈ 0.22 pp. | 0.65% |
| F PYTHON IMPLEMENTATION | 28 | ≈ 3.43 pp. | 10.09% |
| G INTEGRATION WITH RECURSIVE REJECT SAMPLING IN THE MULTI-DRAFT SETUP | 32 | ≈ 1 pp. | 2.94% |
| H COMPUTATION EFFICIENCY | 33 | ≈ 1.89 pp. | 5.56% |
All detected figure and table locations
Argument and organization
- Tokenwise recovery as a baseline
Derives the familiar accept/resample decomposition before extending it to branches.
- Naive hierarchy then capped hierarchy
Separates correctness intuition from the computationally feasible algorithm.
- Proofs, examples and implementation
Connects symbolic conditions to a concrete token sequence and hardware measurements.
Problem, claim and contribution
Joint intractability is named as the specific bottleneck, which distinguishes a verifier contribution from another draft-model improvement.
Section 1, p. 1 · Main paper
Argument and section order
Two adjacent algorithms expose exactly what changes between the costly naive construction and the capped method.
Algorithms 1–2, p. 5 · Main paper
Figures, captions and visual explanation
A backward-scan schematic uses distinct arrows for rejection and corrective sampling; its caption describes the accepted prefix and the single resampling location.
Figure 1, p. 2 · Main paper
Tables, comparisons and evidence
Tables keep hardware-independent tokens per target step separate from tokens per second, avoiding an automatic equivalence between acceptance and latency.
Tables 1–4, pp. 9–10 · Main paper
Appendix and reproducibility
The supplement includes a numerical recovery example, full proof route, Python listings, multi-draft pseudocode and component timing, making distinct verification levels accessible.
Appendices A–H, pp. 13–34 · Main paper
Clarity and writing conventions
The EAGLE integration paragraph qualifies the headline speedup: it keeps first-token acceptance and attributes gains largely to implementation, rather than stronger acceptance theory.
Section 6.2, p. 10 · Main paper
What to reuse—and what not to infer
Transferable lesson: Present a theoretically simple but impractical algorithm first, then show the exact modification that removes its overhead; report acceptance and measured latency separately.
Boundary: Do not attach the standalone lossless guarantee to every integration. The EAGLE experiment keeps a non-lossless first-token convention; the printed code is illustrative and includes unresolved variables, so it is not a verified executable artifact.
Apply this lesson using the argument and evidence worksheet.
Inspection record and sources
- Checked
- 2026-09-19
- Reading status
- Full text + selected visuals inspected
- Main text
- Pages 1–10, Sections 1–7, including all definitions, algorithms and worked example
- Appendix / supplement
- Pages 13–34, Appendices A–H: proofs, expected acceptance, extended experiments, code listings, multi-draft algorithm and runtime accounting
- Visually inspected PDF pages
- 2, 10
- ICLR 2026 final proceedings · 34 pages