pith. sign in

arxiv: 2606.01304 · v2 · pith:SMSSSSHWnew · submitted 2026-05-31 · 💻 cs.LG

When Hard Negatives Hurt: Bridging the Generative-Discriminative Gap in Hard Negative Synthesis for Retrieval

Pith reviewed 2026-06-28 17:08 UTC · model grok-4.3

classification 💻 cs.LG
keywords hard negative synthesiscontrastive learninginformation retrievalLLM generationgenerative-discriminative gapcounterfactual perturbationshortcut learning
0
0 comments X

The pith

Naively adding LLM-generated negatives to contrastive retrieval training often degrades performance because generation favors fluent text over strategic boundary violations.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper establishes that LLM-based hard negative synthesis introduces a generative-discriminative gap that actively harms retriever optimization. LLM outputs tend to be plausible and on-topic but rarely violate the exact information requirements that define relevance at the decision boundary. This leads to two failure modes: generation that ignores query needs and produces no useful contrast, plus distributional shortcuts that let the model distinguish synthetic negatives by origin rather than content. To close the gap the authors introduce CausalNeg, which first decomposes relevance via chain-of-thought into explicit requirements and then perturbs individual requirements to create negatives of controlled hardness. A second training module maximizes entropy across similarity scores to block shortcut learning. If correct, the work shows that synthetic negatives can outperform corpus-mined ones only when hardness is made explicit and source artifacts are suppressed.

Core claim

The root cause of performance degradation when using LLM-generated negatives is the generative-discriminative gap: generation optimizes for fluent, plausible text while contrastive learning requires negatives that strategically violate relevance at the decision boundary. This manifests as discriminative-agnostic generation, where the LLM lacks an explicit model of query information needs, and source-dependent shortcuts, where the model exploits origin artifacts rather than relevance. CausalNeg addresses both by (1) CoT-guided counterfactual perturbation that decomposes a document's relevance into explicit information requirements and surgically violates individual ones, and (2) query-view en

What carries the argument

CausalNeg, whose two modules are CoT-guided counterfactual perturbation (decomposes relevance into explicit requirements then violates them individually) and query-view entropy maximization (disperses negatives to suppress source shortcuts).

If this is right

  • Negatives with explicitly controlled hardness supply genuine contrastive signal instead of generic or drifted text.
  • Suppressing source-identity shortcuts prevents gradient drift that corrupts the similarity space.
  • Synthetic negatives become a viable alternative to corpus mining once the generative-discriminative mismatch is removed.
  • The same perturbation approach can be applied at inference time to generate diagnostic test cases for retriever evaluation.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same decomposition-plus-violation pattern could be tested on other generative data-augmentation tasks such as synthetic query generation or paraphrase creation.
  • If the entropy-maximization step is removed, shortcut exploitation should reappear and performance should fall back toward naive generation levels.
  • The method assumes access to a capable LLM for CoT reasoning; weaker generators may not produce usable requirement lists and could widen the gap instead of closing it.

Load-bearing premise

Chain-of-thought decomposition can reliably break a document's relevance into explicit information requirements that can then be violated one at a time to produce negatives of controlled, interpretable hardness.

What would settle it

On a standard retrieval benchmark, training with CausalNeg-generated negatives yields no improvement or a clear drop relative to both corpus-mined hard negatives and naive LLM negatives.

Figures

Figures reproduced from arXiv: 2606.01304 by Fengyuan Lu, Gang Wang, Hai-Tao Zheng, Jieming Zhu, Jingyu Li, Jiwei Tang, Kuicai Dong, Qianhui Zhu, Wang Jiaheng, Xiaopeng Li, Zhaocheng Du, Zhicheng Zhang.

Figure 1
Figure 1. Figure 1: Illustrative comparison of negative types. (a) Mined negatives are constrained by corpus availability and suffer [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 3
Figure 3. Figure 3: Training dynamics under mixed negatives. (a) Per [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Overview of the CausalNeg. (Left) CoT-guided generation decomposes query into a conjunction of information requirements and applies counterfactual perturbations to produce diverse hard negatives. (Right) Entropy-regularized training maximizes the entropy of generated negatives under the query-conditioned similarity distribution, suppressing source￾dependent shortcuts. Gradients from the entropy loss propag… view at source ↗
Figure 5
Figure 5. Figure 5: Scaling behavior of CoT-generated negatives on [PITH_FULL_IMAGE:figures/full_fig_p009_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Embedding space analysis of CausalNeg generated negatives: (a) cosine similarity distribution; (b) TriMAP vi￾sualization with HDBSCAN cluster assignments. Compared with vanilla generation (Figures 2a and 2b), CoT-generated negatives integrate more naturally with other document types. similar to the positive but merely negating keywords, rather than constructing semantically proximate alternatives with dist… view at source ↗
Figure 7
Figure 7. Figure 7: PCA, t-SNE, and UMAP visualization of document embeddings for vanilla generated negatives. Generated negatives [PITH_FULL_IMAGE:figures/full_fig_p013_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: PCA, t-SNE, and UMAP visualization for CausalNeg generated negatives. The pure cluster phenomenon is largely eliminated; generated negatives intermix with other document types across all projections. Nonetheless, all tested values improve over the baseline, indicating that the method is not sensitive to precise temperature tuning. Entropy loss weight 𝜆. Varying 𝜆 ∈ {0.01, 0.05, 0.1, 0.2} while fixing 𝜏ent … view at source ↗
Figure 9
Figure 9. Figure 9: Condensed Step 2 prompt template for information [PITH_FULL_IMAGE:figures/full_fig_p014_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Condensed Step 3 prompt template for constrained [PITH_FULL_IMAGE:figures/full_fig_p014_10.png] view at source ↗
read the original abstract

Hard negative mining has become the dominant strategy for training retrievers, yet it faces intrinsic limitations: negatives are bounded by corpus availability, selected by retriever score rather than diagnostic value, and increasingly contaminated by false positives as the retriever improves. LLM-based synthesis offers a principled alternative, where negatives that are unconstrained, targeted, and free from false positive risk. But we show that naively incorporating generated negatives into contrastive learning often degrades retrieval performance. We identify and formalize the root cause as a generative-discriminative gap: LLM generation optimizes for fluent, plausible text, while contrastive learning demands strategic violations of relevance at the decision boundary. Our analysis reveals two compounding failure modes: discriminative-agnostic generation, where the LLM lacks an explicit model of query information needs and defaults to generic or topic-drifted text that provides no contrastive signal; and source-dependent shortcuts, where distributional artifacts enable the model to distinguish negatives by origin rather than relevance, causing gradient drift that actively corrupts optimization. To close this gap, we propose CausalNeg consisting of two main modules: (1) CoT-guided counterfactual perturbation for data construction: decomposes why a document satisfies a query into explicit information requirements, then surgically violates individual requirements to construct negatives with controlled, interpretable hardness. (2) Query-view entropy maximization during training: disperses generated negatives across the similarity spectrum, minimizing the mutual information between source identity and similarity scores to suppress shortcut exploitation. We make our code publicly available at https://github.com/mzhangzhicheng/CausalNeg.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 1 minor

Summary. The paper claims that naively incorporating LLM-generated hard negatives into contrastive learning for retrieval often degrades performance. It identifies the root cause as a generative-discriminative gap, where LLM generation optimizes for fluent text while contrastive learning requires strategic relevance violations at the decision boundary. Two failure modes are formalized: discriminative-agnostic generation (lacking explicit query information needs) and source-dependent shortcuts (enabling distinction by origin). To close the gap, CausalNeg is proposed with two modules: (1) CoT-guided counterfactual perturbation, which decomposes document relevance into explicit information requirements and surgically violates individual ones for controlled hardness; (2) query-view entropy maximization during training to disperse negatives across the similarity spectrum and minimize mutual information between source identity and scores. Public code is released.

Significance. If the modules prove effective, the work addresses a practical limitation in hard negative synthesis for retrieval, offering a construction that supplies genuine contrastive signal rather than fluent but non-diagnostic text. The public code release is a clear strength supporting reproducibility.

major comments (1)
  1. [CoT-guided counterfactual perturbation module] The description of the CoT-guided counterfactual perturbation module: the central claim that this decomposition yields negatives with controlled, interpretable hardness aligned to the retriever decision boundary is load-bearing, yet the manuscript provides no independent verification (e.g., human evaluation of decomposition accuracy or ablation on boundary alignment) of whether the CoT step avoids inheriting the same LLM limitations on modeling query information needs that the paper itself diagnoses as the root problem.
minor comments (1)
  1. [Abstract] Abstract: a brief quantitative summary of the observed degradation from naive generation and the gains from CausalNeg would strengthen the presentation of the core claims.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the constructive feedback. We address the major comment below.

read point-by-point responses
  1. Referee: [CoT-guided counterfactual perturbation module] The description of the CoT-guided counterfactual perturbation module: the central claim that this decomposition yields negatives with controlled, interpretable hardness aligned to the retriever decision boundary is load-bearing, yet the manuscript provides no independent verification (e.g., human evaluation of decomposition accuracy or ablation on boundary alignment) of whether the CoT step avoids inheriting the same LLM limitations on modeling query information needs that the paper itself diagnoses as the root problem.

    Authors: We agree that the manuscript relies primarily on downstream retrieval metrics and module ablations rather than direct human evaluation of decomposition accuracy or explicit measurements of decision-boundary alignment. The empirical gains from CausalNeg over naive LLM generation provide indirect support that the CoT step produces more diagnostic negatives, but this does not constitute independent verification of the decomposition quality itself. In the revised manuscript we will add qualitative examples of the CoT decompositions together with an extended discussion of the approach's dependence on LLM reasoning fidelity and its relation to the diagnosed generative-discriminative gap. revision: partial

Circularity Check

0 steps flagged

No significant circularity; derivation is self-contained

full rationale

The paper introduces CausalNeg as a new construction with two modules (CoT-guided counterfactual perturbation for data construction and query-view entropy maximization during training) to address an identified generative-discriminative gap. No equations, derivations, or fitted parameters are presented that reduce by construction to inputs, self-definitions, or self-citation chains. The central claims rest on the proposed method and public code rather than any load-bearing self-referential step or renamed known result. This is the expected outcome for a methods paper without mathematical self-reference.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The paper rests on the standard domain assumption that contrastive learning for retrieval benefits from hard negatives positioned at the decision boundary and on the assumption that LLMs can follow chain-of-thought instructions to decompose relevance. No free parameters or invented entities are described in the abstract.

axioms (1)
  • domain assumption Contrastive learning for retrieval improves when supplied with hard negatives that lie near the relevance decision boundary.
    This is the implicit premise behind both the identified failure modes and the design of CausalNeg.

pith-pipeline@v0.9.1-grok · 5862 in / 1318 out tokens · 31129 ms · 2026-06-28T17:08:35.278532+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Reference graph

Works this paper leans on

64 extracted references · 29 canonical work pages · 4 internal anchors

  1. [1]

    Luiz Bonifacio, Hugo Abonizio, Marzieh Fadaee, and Rodrigo Nogueira. 2022. InPars: Unsupervised Dataset Generation for Information Retrieval. InProceedings of the 45th International ACM SIGIR Conference on Research and Development in Information Retrieval(Madrid, Spain)(SIGIR ’22). Association for Computing Machinery, New York, NY, USA, 2387–2392. doi:10....

  2. [2]

    Luiz Henrique Bonifacio, Israel Campiotti, Roberto Lotufo, and Rodrigo Nogueira

  3. [3]

    arXiv:2108.13897(2021)

    mMARCO: A Multilingual Version of MS MARCO Passage Ranking Dataset. arXiv:2108.13897(2021)

  4. [4]

    Ricardo JGB Campello, Davoud Moulavi, and Jörg Sander. 2013. Density-based clustering based on hierarchical density estimates. InPacific-Asia conference on knowledge discovery and data mining. Springer, 160–172

  5. [5]

    Jianlyu Chen, Shitao Xiao, Peitian Zhang, Kun Luo, Defu Lian, and Zheng Liu

  6. [6]

    InFindings of the As- sociation for Computational Linguistics: ACL 2024, Lun-Wei Ku, Andre Martins, and Vivek Srikumar (Eds.)

    M3-Embedding: Multi-Linguality, Multi-Functionality, Multi-Granularity Text Embeddings Through Self-Knowledge Distillation. InFindings of the As- sociation for Computational Linguistics: ACL 2024, Lun-Wei Ku, Andre Martins, and Vivek Srikumar (Eds.). Association for Computational Linguistics, Bangkok, Thailand, 2318–2335. doi:10.18653/v1/2024.findings-acl.137

  7. [7]

    Ting Chen, Simon Kornblith, Mohammad Norouzi, and Geoffrey Hinton. 2020. A simple framework for contrastive learning of visual representations. InProceed- ings of the 37th International Conference on Machine Learning (ICML’20). JMLR.org, Article 149, 11 pages

  8. [8]

    Kuicai Dong, Yujing Chang, Derrick Goh Xin Deik, Dexun Li, Ruiming Tang, and Yong Liu. 2025. MMDocIR: Benchmarking Multimodal Retrieval for Long Documents. InProceedings of the 2025 Conference on Empirical Methods in Nat- ural Language Processing, Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, and Violet Peng (Eds.). Association for Comput...

  9. [9]

    Kuicai Dong, Yujing Chang, Shijie Huang, Yasheng Wang, Ruiming Tang, and Yong Liu. 2025. Benchmarking Retrieval-Augmented Multimodal Generation for Document Question Answering. arXiv:2505.16470 [cs.IR] https://arxiv.org/abs/ 2505.16470

  10. [10]

    Kuicai Dong, Derrick Goh Xin Deik, Yi Quan Lee, Hao Zhang, Xiangyang Li, Cong Zhang, and Yong Liu. 2024. MC-indexing: Effective Long Document Re- trieval via Multi-view Content-aware Indexing. InFindings of the Association KDD ’26, August 09–13, 2026, Jeju Island, Republic of Korea Zhang et al. for Computational Linguistics: EMNLP 2024, Yaser Al-Onaizan, ...

  11. [11]

    Kuicai Dong, Shurui Huang, Fangda Ye, Wei Han, Zhi Zhang, Dexun Li, Wen- jun Li, Qu Yang, Gang Wang, Yichao Wang, Chen Zhang, and Yong Liu. 2025. Doc-Researcher: A Unified System for Multimodal Document Parsing and Deep Research. arXiv:2510.21603 [cs.IR] https://arxiv.org/abs/2510.21603

  12. [12]

    Zeyu Gan and Yong Liu. 2025. Towards a Theoretical Understanding of Synthetic Data in LLM Post-Training: A Reverse-Bottleneck Perspective. InThe Thirteenth International Conference on Learning Representations. https://openreview.net/ forum?id=UxkznlcnHf

  13. [13]

    Pengyue Jia, Derong Xu, Xiaopeng Li, Zhaocheng Du, Xiangyang Li, Yichao Wang, Yuhao Wang, Qidong Liu, Maolin Wang, Huifeng Guo, Ruiming Tang, and Xiangyu Zhao. 2025. Bridging Relevance and Reasoning: Rationale Distillation in Retrieval-Augmented Generation. InFindings of the Association for Computational Linguistics: ACL 2025, Wanxiang Che, Joyce Nabende,...

  14. [14]

    Mandar Joshi, Eunsol Choi, Daniel Weld, and Luke Zettlemoyer. 2017. TriviaQA: A Large Scale Distantly Supervised Challenge Dataset for Reading Comprehension. InProceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), Regina Barzilay and Min-Yen Kan (Eds.). Association for Computational Linguistics, V...

  15. [15]

    Jaehun Jung, Seungju Han, Ximing Lu, Skyler Hallinan, David Acuna, Shrimai Prabhumoye, Mostofa Patwary, Mohammad Shoeybi, Bryan Catanzaro, and Yejin Choi. 2025. Prismatic Synthesis: Gradient-based Data Diversification Boosts Gen- eralization in LLM Reasoning. InThe Thirty-ninth Annual Conference on Neural Information Processing Systems. https://openreview...

  16. [16]

    Vladimir Karpukhin, Barlas Oguz, Sewon Min, Patrick Lewis, Ledell Wu, Sergey Edunov, Danqi Chen, and Wen-tau Yih. 2020. Dense Passage Retrieval for Open- Domain Question Answering. InProceedings of the 2020 Conference on Empirical Methods in Natural Language Processing (EMNLP), Bonnie Webber, Trevor Cohn, Yulan He, and Yang Liu (Eds.). Association for Com...

  17. [17]

    Dai, Jakob Uszkoreit, Quoc Le, and Slav Petrov

    Tom Kwiatkowski, Jennimaria Palomaki, Olivia Redfield, Michael Collins, Ankur Parikh, Chris Alberti, Danielle Epstein, Illia Polosukhin, Jacob Devlin, Kenton Lee, Kristina Toutanova, Llion Jones, Matthew Kelcey, Ming-Wei Chang, Andrew M. Dai, Jakob Uszkoreit, Quoc Le, and Slav Petrov. 2019. Natural Questions: A Benchmark for Question Answering Research.Tr...

  18. [18]

    Jinhyuk Lee, Feiyang Chen, Sahil Dua, Daniel Cer, Madhuri Shanbhogue, Iftekhar Naim, Gustavo Hernández Ábrego, Zhe Li, Kaifeng Chen, Henrique Schechter Vera, Xiaoqi Ren, Shanfeng Zhang, Daniel Salz, Michael Boratko, Jay Han, Blair Chen, Shuo Huang, Vikram Rao, Paul Suganthan, Feng Han, Andreas Doumanoglou, Nithi Gupta, Fedor Moiseev, Cathy Yip, Aashi Jain...

  19. [19]

    Xiangyang Li, Kuicai Dong, Yi Quan Lee, Wei Xia, Hao Zhang, Xinyi Dai, Yasheng Wang, and Ruiming Tang. 2025. CoIR: A Comprehensive Benchmark for Code Information Retrieval Models. InProceedings of the 63rd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), Wanxiang Che, Joyce Nabende, Ekaterina Shutova, and Mohammad T...

  20. [20]

    Xiaopeng Li, Xiangyang Li, Hao Zhang, Zhaocheng Du, Pengyue Jia, Yichao Wang, Xiangyu Zhao, Huifeng Guo, and Ruiming Tang. 2024. SyNeg: LLM- Driven Synthetic Hard-Negatives for Dense Retrieval. arXiv:2412.17250 [cs.IR] https://arxiv.org/abs/2412.17250

  21. [21]

    Zhiteng Li, Lele Chen, Jerone Andrews, Yunhao Ba, Yulun Zhang, and Alice Xiang. 2025. GenDataAgent: On-the-fly Dataset Augmentation with Synthetic Data. InInternational Conference on Learning Represen- tations, Y. Yue, A. Garg, N. Peng, F. Sha, and R. Yu (Eds.), Vol. 2025. 48578–48598. https://proceedings.iclr.cc/paper_files/paper/2025/file/ 79081c9548270...

  22. [22]

    Lin Long, Rui Wang, Ruixuan Xiao, Junbo Zhao, Xiao Ding, Gang Chen, and Haobo Wang. 2024. On LLMs-Driven Synthetic Data Generation, Curation, and Evaluation: A Survey. InFindings of the Association for Computational Linguistics: ACL 2024, Lun-Wei Ku, Andre Martins, and Vivek Srikumar (Eds.). Association for Computational Linguistics, Bangkok, Thailand, 11...

  23. [23]

    Moreira, Radek Osmulski, Mengyao Xu, Ronay Ak, Benedikt Schifferer, and Even Oldridge

    Gabriel de Souza P. Moreira, Radek Osmulski, Mengyao Xu, Ronay Ak, Benedikt Schifferer, and Even Oldridge. 2025. Improving Text Embedding Models with Positive-aware Hard-negative Mining. InProceedings of the 34th ACM Interna- tional Conference on Information and Knowledge Management(Seoul, Republic of Korea)(CIKM ’25). Association for Computing Machinery,...

  24. [24]

    Le, Long Tran-Thanh, and Khoat Than

    Lan-Cuong Nguyen, Quan Nguyen-Tri, Bang Tran Khanh, Dung D. Le, Long Tran-Thanh, and Khoat Than. 2025. Provably Improving Generalization of Few- shot models with Synthetic Data. InForty-second International Conference on Machine Learning. https://openreview.net/forum?id=L6U7nYc4ah

  25. [25]

    Tri Nguyen, Mir Rosenberg, Xia Song, Jianfeng Gao, Saurabh Tiwary, Rangan Majumder, and Li Deng. 2016. MS MARCO: A Human Generated MAchine Reading COmprehension Dataset. InProceedings of the Workshop on Cogni- tive Computation: Integrating neural and symbolic approaches 2016 co-located with the 30th Annual Conference on Neural Information Processing Syste...

  26. [26]

    Yingqi Qu, Yuchen Ding, Jing Liu, Kai Liu, Ruiyang Ren, Wayne Xin Zhao, Daxiang Dong, Hua Wu, and Haifeng Wang. 2021. RocketQA: An Optimized Training Approach to Dense Passage Retrieval for Open-Domain Question An- swering. InProceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language T...

  27. [27]

    Jiyuan Ren, Zhaocheng Du, Zhihao Wen, Qinglin Jia, Sunhao Dai, Chuhan Wu, and Zhenhua Dong. 2025. Few-shot LLM Synthetic Data with Distribution Matching. InCompanion Proceedings of the ACM on Web Conference 2025(Sydney NSW, Australia)(WWW ’25). Association for Computing Machinery, New York, NY, USA, 432–441. doi:10.1145/3701716.3715245

  28. [28]

    Stephen E Robertson and Steve Walker. 1994. Some simple effective approxi- mations to the 2-poisson model for probabilistic weighted retrieval. InSIGIR’94: Proceedings of the Seventeenth Annual International ACM-SIGIR Conference on Research and Development in Information Retrieval, organised by Dublin City University. Springer, 232–241

  29. [29]

    Joshua David Robinson, Ching-Yao Chuang, Suvrit Sra, and Stefanie Jegelka. 2021. Contrastive Learning with Hard Negative Samples. InInternational Conference on Learning Representations. https://openreview.net/forum?id=CR1XOQ0UTh-

  30. [30]

    Ilia Shumailov, Zakhar Shumaylov, Yiren Zhao, Nicolas Papernot, Ross Anderson, and Yarin Gal. 2024. AI models collapse when trained on recursively generated data.Nature631, 8022 (2024), 755–759

  31. [31]

    Morris, Jyoti Aneja, Alexander Rush, and Jianfeng Gao

    Chandan Singh, John X. Morris, Jyoti Aneja, Alexander Rush, and Jianfeng Gao

  32. [32]

    Explaining Data Patterns in Natural Language with Language Models. In Proceedings of the 6th BlackboxNLP Workshop: Analyzing and Interpreting Neural Networks for NLP, Yonatan Belinkov, Sophie Hao, Jaap Jumelet, Najoung Kim, Arya McCarthy, and Hosein Mohebbi (Eds.). Association for Computational Linguistics, Singapore, 31–55. doi:10.18653/v1/2023.blackboxnlp-1.3

  33. [33]

    Smith, and Yejin Choi

    Swabha Swayamdipta, Roy Schwartz, Nicholas Lourie, Yizhong Wang, Hannaneh Hajishirzi, Noah A. Smith, and Yejin Choi. 2020. Dataset Cartography: Mapping and Diagnosing Datasets with Training Dynamics. InProceedings of the 2020 Conference on Empirical Methods in Natural Language Processing (EMNLP), Bonnie Webber, Trevor Cohn, Yulan He, and Yang Liu (Eds.). ...

  34. [34]

    Jiwei Tang, Zhijing Huang, Xinyu Zhang, Chen Jason Zhang, Jianxing Yu, Libin Zheng, Rui Meng, and Jian Yin. 2026. Beyond Position Bias: Shifting Context Compression from Position-Driven to Semantic-Driven. arXiv:2605.09463 [cs.CL] https://arxiv.org/abs/2605.09463

  35. [35]

    Jiwei Tang, Shilei Liu, Zhicheng Zhang, Qingsong Lv, Runsong Zhao, Tingwei Lu, Langming Liu, Haibin Chen, Yujin Yuan, Hai-Tao Zheng, Wenbo Su, and Bo Zheng

  36. [36]

    arXiv:2602.01840 [cs.CL] https://arxiv.org/abs/2602.01840

    Read As Human: Compressing Context via Parallelizable Close Reading and Skimming. arXiv:2602.01840 [cs.CL] https://arxiv.org/abs/2602.01840

  37. [37]

    Jiwei Tang, Shilei Liu, Zhicheng Zhang, Yujin Yuan, Libin Zheng, Wenbo Su, and Bo Zheng. 2026. COMI: Coarse-to-fine Context Compression via Marginal Information Gain. InThe Fourteenth International Conference on Learning Repre- sentations. https://openreview.net/forum?id=OGDIXDfaN4

  38. [38]

    Jiwei Tang, Jin Xu, Tingwei Lu, Zhicheng Zhang, Yiming Zhao, Lin Hai, and Hai-Tao Zheng. 2025. Perception Compressor: A Training-Free Prompt Com- pression Framework in Long Context Scenarios. InFindings of the Association for Computational Linguistics: NAACL 2025, Luis Chiruzzo, Alan Ritter, and Lu Wang (Eds.). Association for Computational Linguistics, A...

  39. [39]

    Jiwei Tang, Zhicheng Zhang, Shunlong Wu, Jingheng Ye, Lichen Bai, Zitai Wang, Tingwei Lu, Lin Hai, Yiming Zhao, Hai-Tao Zheng, and Hong-Gee Kim. 2026. GMSA: Enhancing Context Compression via Group Merging and Layer Semantic Alignment. arXiv:2505.12215 [cs.CL] https://arxiv.org/abs/2505.12215

  40. [40]

    Nandan Thakur, Nils Reimers, Andreas Rücklé, Abhishek Srivastava, and Iryna Gurevych. 2021. BEIR: A Heterogeneous Benchmark for Zero-shot Evaluation of Information Retrieval Models. InThirty-fifth Conference on Neural Information When Hard Negatives Hurt: Bridging the Generative- Discriminative Gap in Hard Negative Synthesis for Retrieval KDD ’26, August ...

  41. [41]

    Aaron van den Oord, Yazhe Li, and Oriol Vinyals. 2019. Representation Learning with Contrastive Predictive Coding. arXiv:1807.03748 [cs.LG] https://arxiv.org/ abs/1807.03748

  42. [42]

    Liang Wang, Nan Yang, Xiaolong Huang, Linjun Yang, Rangan Majumder, and Furu Wei. 2024. Improving text embeddings with large language models. In Proceedings of the 62nd Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers). 11897–11916

  43. [43]

    Chi, Quoc V

    Jason Wei, Xuezhi Wang, Dale Schuurmans, Maarten Bosma, Brian Ichter, Fei Xia, Ed H. Chi, Quoc V. Le, and Denny Zhou. 2022. Chain-of-thought prompting elicits reasoning in large language models. InProceedings of the 36th International Conference on Neural Information Processing Systems(New Orleans, LA, USA) (NIPS ’22). Curran Associates Inc., Red Hook, NY...

  44. [44]

    Bennett, Junaid Ahmed, and Arnold Overwijk

    Lee Xiong, Chenyan Xiong, Ye Li, Kwok-Fung Tang, Jialin Liu, Paul N. Bennett, Junaid Ahmed, and Arnold Overwijk. 2021. Approximate Nearest Neighbor Neg- ative Contrastive Learning for Dense Text Retrieval. InInternational Conference on Learning Representations. https://openreview.net/forum?id=zeFrfgyZln

  45. [45]

    Zhilin Yang, Peng Qi, Saizheng Zhang, Yoshua Bengio, William Cohen, Ruslan Salakhutdinov, and Christopher D. Manning. 2018. HotpotQA: A Dataset for Diverse, Explainable Multi-hop Question Answering. InProceedings of the 2018 Conference on Empirical Methods in Natural Language Processing, Ellen Riloff, David Chiang, Julia Hockenmaier, and Jun’ichi Tsujii (...

  46. [46]

    Zhen Yang, Zhou Shao, Yuxiao Dong, and Jie Tang. 2024. TriSampler: a better negative sampling principle for dense retrieval. InProceedings of the Thirty- Eighth AAAI Conference on Artificial Intelligence and Thirty-Sixth Conference on Innovative Applications of Artificial Intelligence and Fourteenth Symposium on Educational Advances in Artificial Intellig...

  47. [47]

    Andrew Yates, Rodrigo Nogueira, and Jimmy Lin. 2021. Pretrained Transformers for Text Ranking: BERT and Beyond. InProceedings of the 2021 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies: Tutorials, Greg Kondrak, Kalina Bontcheva, and Dan Gillick (Eds.). Association for Computational Li...

  48. [48]

    Jingtao Zhan, Jiaxin Mao, Yiqun Liu, Jiafeng Guo, Min Zhang, and Shaop- ing Ma. 2021. Optimizing Dense Retrieval Model Training with Hard Neg- atives. InProceedings of the 44th International ACM SIGIR Conference on Re- search and Development in Information Retrieval(Virtual Event, Canada)(SIGIR ’21). Association for Computing Machinery, New York, NY, USA,...

  49. [49]

    Yanzhao Zhang, Mingxin Li, Dingkun Long, Xin Zhang, Huan Lin, Baosong Yang, Pengjun Xie, An Yang, Dayiheng Liu, Junyang Lin, Fei Huang, and Jingren Zhou

  50. [50]

    Qwen3 Embedding: Advancing Text Embedding and Reranking Through Foundation Models.arXiv preprint arXiv:2506.05176(2025)

  51. [51]

    Zhicheng Zhang, Zhaocheng Du, Jieming Zhu, Jiwei Tang, Fengyuan Lu, Wang Jiaheng, Song-Li Wu, Qianhui Zhu, Jingyu Li, Hai-Tao Zheng, and Zhenhua Dong

  52. [52]

    arXiv:2601.19142 [cs.AI] https://arxiv.org/abs/2601

    Length-Adaptive Interest Network for Balancing Long and Short Sequence Modeling in CTR Prediction. arXiv:2601.19142 [cs.AI] https://arxiv.org/abs/2601. 19142

  53. [53]

    Yuze Zhao, Jintao Huang, Jinghan Hu, Xingjun Wang, Yunlin Mao, Daoze Zhang, Zeyinzi Jiang, Zhikai Wu, Baole Ai, Ang Wang, Wenmeng Zhou, and Yingda Chen

  54. [54]

    SWIFT: a scalable lightweight infrastructure for fine-tuning. InProceedings of the Thirty-Ninth AAAI Conference on Artificial Intelligence and Thirty-Seventh Conference on Innovative Applications of Artificial Intelligence and Fifteenth Sympo- sium on Educational Advances in Artificial Intelligence (AAAI’25/IAAI’25/EAAI’25). AAAI Press, Article 3485, 3 pa...

  55. [55]

    Ruiqi Zhong, Charlie Snell, Dan Klein, and Jacob Steinhardt. 2022. Describing Differences between Text Distributions with Natural Language. InProceedings of the 39th International Conference on Machine Learning (Proceedings of Machine Learning Research, Vol. 162), Kamalika Chaudhuri, Stefanie Jegelka, Le Song, Csaba Szepesvari, Gang Niu, and Sivan Sabato ...

  56. [56]

    Kun Zhou, Yeyun Gong, Xiao Liu, Wayne Xin Zhao, Yelong Shen, Anlei Dong, Jingwen Lu, Rangan Majumder, Ji-rong Wen, and Nan Duan. 2022. SimANS: Simple Ambiguous Negatives Sampling for Dense Text Retrieval. InProceedings of the 2022 Conference on Empirical Methods in Natural Language Processing: Industry Track, Yunyao Li and Angeliki Lazaridou (Eds.). Assoc...

  57. [57]

    good” and “bad

    Xuekai Zhu, Daixuan Cheng, Hengli Li, Kaiyan Zhang, Ermo Hua, Xingtai Lv, Ning Ding, Zhouhan Lin, Zilong Zheng, and Bowen Zhou. 2025. How to Synthe- size Text Data without Model Collapse?. InForty-second International Conference on Machine Learning. https://openreview.net/forum?id=ihUi76a4u7 A Detailed LLM Diagnostic Results This section provides comprehe...

  58. [58]

    Query information need (one sentence)

  59. [59]

    How positive sample satisfies it (one sentence)

  60. [60]

    Answer boundary: what counts as answering

  61. [61]

    Chain of Thought: Decompose into 4–8 reasoning nodes, each with facet_type (information_need / entity / attribute / constraint / reasoning / style), content, and critical flag. Part 2: Design Disruption Strategies For each critical node, design 2–3 strategies: - entity_shift: entity replacement - intent_drift: information need drift - constraint_violation...

  62. [62]

    Cannot answer the query in any form (correct, incorrect, or partial)

  63. [63]

    Prioritize rewriting candidate negatives; preserve their style and noise

  64. [64]

    {Dataset-specific writing style constraints} Output: JSON with node_id, strategy_id, generated text, and break_explanation

    Only generate from scratch if no candidates fit; simulate real corpus style. {Dataset-specific writing style constraints} Output: JSON with node_id, strategy_id, generated text, and break_explanation. Figure 10: Condensed Step 3 prompt template for constrained hard negative generation. query are used by default for fair comparison with vanilla gener- atio...