Zeyu Liu
Author directory2026
EvalMem: An Operation-Level Diagnostic Framework for Long-Term Memory Systems
Zeyu Liu | Jian Zhong | Rongduo Han | Ziyang Wu | Shunye Tang | Chenghao He | Yaxuan Yang | Yihang Qiu | Ailing Wang | Xiao Liang | Guohuan Xie | Xiaokang Xue | Gongchen Li | Haining Zhang | Wei Wang
Findings of the Association for Computational Linguistics: EMNLP 2026
Zeyu Liu | Jian Zhong | Rongduo Han | Ziyang Wu | Shunye Tang | Chenghao He | Yaxuan Yang | Yihang Qiu | Ailing Wang | Xiao Liang | Guohuan Xie | Xiaokang Xue | Gongchen Li | Haining Zhang | Wei Wang
Findings of the Association for Computational Linguistics: EMNLP 2026
Long-horizon interactions with LLM-based assistants require memory systems that preserve and update user states, preferences, and interaction histories. Existing evaluations report end-to-end QA accuracy and cannot determine whether errors arise from encoding, retrieval, or generation. We introduce **EvalMem**, an operation-level diagnostic framework with three parallel Examiners. For each query, the Encoding Examiner checks whether the target fact is stored, the Retrieval Examiner assesses whether the native retriever returns usable evidence, and the Generation Examiner tests whether the model can answer from oracle evidence. Their outputs form fine-grained multi-label defect codes. To improve store-level diagnosis, we adapt agentic RAG with a recall-first strategy that searches using both the query and source evidence, increasing recall of present evidence on LoCoMo from 70.2% to 95.6%. Evaluations of seven memory systems on LoCoMo, LongMemEval-S, and dynamic DynaMem-Bench identify retrieval as the most frequently attributed failure layer; in default LoCoMo, retrieval defects reach 22.1%, compared with 7.7% for encoding and 6.5% for generation. Guided by this diagnosis, **MemWiki**, a search-friendly auxiliary structure built from each system’s memory export, improves mean accuracy by 2.5 and 2.3 percentage points on LoCoMo and LongMemEval-S, respectively.
2025
LAWCAT: Efficient Distillation from Quadratic to Linear Attention with Convolution across Tokens for Long Context Modeling
Zeyu Liu | Souvik Kundu | Lianghao Jiang | Anni Li | Srikanth Ronanki | Sravan Babu Bodapati | Gourav Datta | Peter Anthony Beerel
Findings of the Association for Computational Linguistics: EMNLP 2025
Zeyu Liu | Souvik Kundu | Lianghao Jiang | Anni Li | Srikanth Ronanki | Sravan Babu Bodapati | Gourav Datta | Peter Anthony Beerel
Findings of the Association for Computational Linguistics: EMNLP 2025
Although transformer architectures have achieved state-of-the-art performance across diverse domains, their quadratic computational complexity with respect to sequence length remains a significant bottleneck, particularly for latency-sensitive long-context applications. While recent linear-complexity alternatives are increasingly powerful, effectively training them from scratch is still resource-intensive. To overcome these limitations, we propose LAWCAT (Linear Attention with Convolution Across Time), a novel linearization framework designed to efficiently transfer the capabilities of pretrained transformers into a performant linear attention architecture. LAWCAT integrates causal Conv1D layers to enhance local dependency modeling and employs normalized gated linear attention to improve generalization across varying context lengths. Our comprehensive evaluations demonstrate that, distilling Mistral-7B with only 1K-length sequences yields over 90% passkey retrieval accuracy up to 22K tokens, significantly extending its effective context window. Similarly, Llama3.2-1B LAWCAT variant achieves competitive performance on S-NIAH 1&2&3 tasks (1K-8K context length) and BABILong benchmark (QA2&QA3, 0K-16K context length), requiring less than 0.1% pre-training tokens compared with pre-training models. Furthermore, LAWCAT exhibits faster prefill speeds than FlashAttention-2 for sequences exceeding 8K tokens. LAWCAT thus provides an efficient pathway to high-performance, long-context linear models suitable for edge deployment, reducing reliance on extensive long-sequence training data and computational resources.
2024
AFLoRA: Adaptive Freezing of Low Rank Adaptation in Parameter Efficient Fine-Tuning of Large Models
Zeyu Liu | Souvik Kundu | Anni Li | Junrui Wan | Lianghao Jiang | Peter Beerel
Proceedings of the 62nd Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)
Zeyu Liu | Souvik Kundu | Anni Li | Junrui Wan | Lianghao Jiang | Peter Beerel
Proceedings of the 62nd Annual Meeting of the Association for Computational Linguistics (Volume 2: Short Papers)
We present a novel Parameter-Efficient Fine-Tuning (PEFT) method, dubbed as Adaptive Freezing of Low-Rank Adaptation (AFLoRA). Specifically, for each pre-trained frozen weight tensor, we add a parallel path of trainable low-rank matrices, namely a down-projection and an up-projection matrix, each of which is followed by a feature transformation vector. Based on a novel freezing score, we incrementally freeze these projection matrices during fine-tuning to reduce the computation and alleviate over-fitting. Our experimental results demonstrate that we can achieve state-of-the-art performance with an average improvement of up to 0.85% as evaluated on the GLUE benchmark while yielding up to 9.5× fewer average trainable parameters. While compared in terms of runtime, AFLoRA can yield up to 1.86× improvement as opposed to similar PEFT alternatives. Besides the practical utility of our approach, we provide insights on the trainability requirements of LoRA paths at different modules and the freezing schedule for the different projection matrices.
2020
Linguistically-Informed Transformations (LIT): A Method for Automatically Generating Contrast Sets
Chuanrong Li | Lin Shengshuo | Zeyu Liu | Xinyi Wu | Xuhui Zhou | Shane Steinert-Threlkeld
Proceedings of the Third BlackboxNLP Workshop on Analyzing and Interpreting Neural Networks for NLP
Chuanrong Li | Lin Shengshuo | Zeyu Liu | Xinyi Wu | Xuhui Zhou | Shane Steinert-Threlkeld
Proceedings of the Third BlackboxNLP Workshop on Analyzing and Interpreting Neural Networks for NLP
Although large-scale pretrained language models, such as BERT and RoBERTa, have achieved superhuman performance on in-distribution test sets, their performance suffers on out-of-distribution test sets (e.g., on contrast sets). Building contrast sets often requires human-expert annotation, which is expensive and hard to create on a large scale. In this work, we propose a Linguistically-Informed Transformation (LIT) method to automatically generate contrast sets, which enables practitioners to explore linguistic phenomena of interests as well as compose different phenomena. Experimenting with our method on SNLI and MNLI shows that current pretrained language models, although being claimed to contain sufficient linguistic knowledge, struggle on our automatically generated contrast sets. Furthermore, we improve models’ performance on the contrast sets by applying LIT to augment the training data, without affecting performance on the original data.
Search
Fix author
Co-authors
- Lianghao Jiang 2
- Souvik Kundu 2
- Anni Li 2
- Peter Beerel 1
- Peter Anthony Beerel 1
- Sravan Babu Bodapati 1
- Gourav Datta 1
- Rongduo Han 1
- Chenghao He 1
- Chuanrong Li 1
- Gongchen Li 1
- Xiao Liang (梁霄) 1
- Yihang Qiu 1
- Srikanth Ronanki 1
- Lin Shengshuo 1
- Shane Steinert-Threlkeld 1
- Shunye Tang 1
- Junrui Wan 1
- Ailing Wang 1
- Wei Wang 1
- Xinyi Wu 1
- Ziyang Wu 1
- Guohuan Xie 1
- Xiaokang Xue 1
- Yaxuan Yang 1
- Haining Zhang 1
- Jian Zhong 1
- Xuhui Zhou 1