Writing study: DOUBT: Decoupled Object-level Understanding and Bridging via vMF-based Trustworthiness for Hallucination Detection in MLLMs
← ICML 2026 oral writing corpus
Kaiqi Chen, Yang Qin, Changhao He, Xi Peng, Peng Hu · Official ICML 2026 oral record
Figure, table and section ledger
Editorial contribution type: Domain-grounded methods & physical systems (primary).
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
- 24 physical pages
- Before references / appendix
- ≈ 9.23 page-equivalents
- Main figures / tables
- 4 / 3
- Attached appendix figures / tables
- 0 / 8
- Attached appendix span
- ≈ 10.91 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 | ≈ 1.42 pp. | 5.92% |
| 2. Related Work | 3 | ≈ 0.6 pp. | 2.5% |
| 3. Method | 3 | ≈ 2.24 pp. | 9.33% |
| 4. Experiment | 5 | ≈ 2.49 pp. | 10.38% |
| 5. Computational Cost Analysis | 8 | ≈ 1.39 pp. | 5.79% |
| 6. Conclusion | 9 | ≈ 0.28 pp. | 1.17% |
| Impact Statement | 10 | ≈ 0.08 pp. | 0.33% |
| Acknowledgments | 10 | ≈ 0.11 pp. | 0.46% |
| References | 10 | ≈ 3.85 pp. | 16.04% |
| A. Hallucination Mitigation through OUB | 14 | ≈ 0.43 pp. | 1.79% |
| B. Performance under Different vMF Parameters | 14 | ≈ 0.29 pp. | 1.21% |
| C. Effect of Introducing a More Capable External Model | 14 | ≈ 0.5 pp. | 2.08% |
| D. Impact of Different Uncertainty Estimation Metrics | 15 | ≈ 0.44 pp. | 1.83% |
| E. Ablation on the Number of Recognized Objects | 15 | ≈ 0.86 pp. | 3.58% |
| F. Hard Case Analysis | 16 | ≈ 0.22 pp. | 0.92% |
| G. Robustness to Stage-2 Prompt Formats | 16 | ≈ 0.9 pp. | 3.75% |
| H. Robustness to Different Semantic Embedding Models | 17 | ≈ 0.59 pp. | 2.46% |
| I. Case Study | 18 | ≈ 6.67 pp. | 27.79% |
All detected figure and table locations
Main text
Argument and organization
- Problem and contribution
Motivates the method with confidently consistent wrong answers, separating diversity induced by a grounding prompt from the reliability statistic used to score the resulting responses.
- Argument sequence
Prompt construction precedes a geometric consistency measure and an explicit binary evaluation rule, followed by component ablations and a separate computational-cost section.
- Evidence and verification
Detection accuracy checks whether the predicted reliability flag agrees with a reference answer's correctness; the separate mitigation appendix measures answer improvement, while hard-case recovery uses a deliberately selected failure subset.
Problem, claim and contribution
Motivates the method with confidently consistent wrong answers, separating diversity induced by a grounding prompt from the reliability statistic used to score the resulting responses.
Introduction and Figure 1, pp. 1-2; Section 3, pp. 3-5 · Main paper
Argument and section order
Prompt construction precedes a geometric consistency measure and an explicit binary evaluation rule, followed by component ablations and a separate computational-cost section.
Sections 3-5, pp. 3-8 · Main paper
Figures, captions and visual explanation
The ablation table retains configurations where removing a component wins locally, and the cost table exposes 21 forward passes plus latency and generated tokens rather than describing training-free operation as cost-free.
Table 2, Figure 3 and Table 3, p. 8; p. 5 metric-definition and p. 8 PNGs inspected · Main paper
Tables, comparisons and evidence
Detection accuracy checks whether the predicted reliability flag agrees with a reference answer's correctness; the separate mitigation appendix measures answer improvement, while hard-case recovery uses a deliberately selected failure subset.
Section 3.4, p. 5; Appendix A, p. 14; F, pp. 16-17 · Main paper
Appendix and reproducibility
Prompt, embedding-model and object-count comparisons expose deployment choices, while selected full response sets let readers inspect how bridging changes variation rather than merely seeing aggregate scores.
Appendices B-H, pp. 14-17; I, pp. 18-24 · Main paper
Clarity and writing conventions
The equation defines flag=1 as non-hallucinatory despite the phrase hallucination flag, so a reusable account must preserve the polarity; the trustworthiness statistic is internal consistency, not a calibrated correctness probability.
Equations 4-6 and Section 3.4, p. 5 · Main paper
What to reuse—and what not to infer
Transferable lesson: Define the target, flag polarity and denominator before presenting detection results, and report inference overhead separately from the absence of model retraining.
Boundary: Consistency can remain wrong, the 39.10% recovery figure concerns a selected semantic-entropy failure subset, and illustrative medical imagery is not clinical validation; black-box prompting also uses an external sentence-embedding model.
Apply this lesson using the argument and evidence worksheet.
Inspection record and sources
- Checked
- 2026-10-07
- Reading status
- Writing-focused manuscript scan + selected visuals inspected
- Main text
- Writing-focused distributed manuscript scan, not exhaustive technical/proof validation. Sections 1-6, pp. 1-9: false-consistency motivation, object-bridged prompting, directional embedding concentration, detection definition, evaluations, ablations, cost and qualitative mitigation.
- Appendix / supplement
- Writing-focused appendix scan; code, data and external assets not executed. Appendices A-I, pp. 14-24: answer mitigation, stronger object-list generators, prompt and hyperparameter robustness, hard-case subsets, embedding choices and extended examples.
- Visually inspected PDF pages
- 5, 8
This is a writing-focused scan of the manuscript and the stated supplementary scope: framing, organization, visual explanation, evidence presentation and wording. It is not a line-by-line proof audit, reproduction of results or exhaustive scientific review.