Xi Ai

Research Interests

Multilingualism and Cross-lingual NLP

• Multilingual, Cross-lingual, and Code-mixed NLP
• Multilingual LLM
• Parity and Consistency in Multilingual Model
• Multilingual Generation and Reasoning
• Multilingual Machine Translation
• Interpretability for Multilingualism

ML for NLP

• Foundational LLM
• Test-time Training
• LLM Efficiency
• RAG
• Implicit Layer and Latent Space

Others

• Computational Linguistics
• Fact Checking

Education

• 2008.09-2012.07， Northumbria University(UK)，BSc
• 2012.09-2014.01， University of Edinburgh(UK)， MSc
• 2018.09-2023.07， Chongqing University(CN)， PhD

Academia Experience

• 2015.05-2016.06，University of Durham(UK)，Research Candidate
• 2023.11-2025.11，National University of Singapore(SG)，Research Fellow
• 2023.11-2025.11，NUSRI-CQ(CN)，Research Fellow

First Authored Publication

• "Are Knowledge and Reference in Multilingual Language Models Cross-Lingually Consistent?"，EMNLP 2025
• "Zero-shot Cross-lingual Alignment for Embedding Initialization"，ACL 2024
• "On-the-fly Cross-lingual Masking in Multilingual Training"，ACL 2023
• "Multilingual Training with Globe Concurrence Information"，ACL 2023
• "Leverage Relaxed Equilibrium for Sequence Modeling"，ACL 2022
• "Vocabulary-informed Language Encoding"，COLING 2022
• "Almost Free Semantic Draft for Neural Machine Translation"，NAACL 2021
• "Empirical Regularization for Synthetic Sentence Pairs in Unsupervised Neural Machine Translation"，AAAI 2021
• "Cross-modal Language Modeling in Multi-motion-informed Context for Lip Reading"，IEEE/ACM Transactions on Audio, Speech and Language Processing (TASLP)
• "M3CHECK: A Demonstration System for Multilingual Multi-clue Multi-Hop Fact-Checking"

Recent Work

• Efficient LLM Pipeline
• Parameterized ICL in Test-time
• Multilingual Parity, Consistency and Trolley problem

Grant

• Research on Parity and consistency in Multilingual LLM，2026.01-2028.12
• Venture Initiation Programme from NUS@SoC，2025 (co-PI with my student)

Service

Promgram Chair

• 7th Workshop on Computational Approaches to Linguistic Code Switching at NAACL 2025

Area Chair

• Multilingualism and Cross-lingual NLP track at ACL and EMNLP
• ML for NLP track at ACL and EMNLP

Reviewer

• ACL, EMNLP, NAACL, AAAI, ICLR, COLING, TASLP, Knowledge-Based Systems, TAFFC

Award

• Outstanding Reviewer ACL 2023
• Distinguished PhD in Chongqing University 2024

Teaching/Tutoring

• Retrieval-Augmented Generation
• Deep Learning for NLP