Qishuai Zhong

Author directory

2026

Large language models are increasingly deployed for personalized interaction, and demographic conditioning via user profiles is a widely adopted strategy for cultural adaptation. We ask whether this approach genuinely serves individual users or achieves accuracy by erasing individual distinctiveness. Studying seven models including frontier GPT-5.1 on the World Values Survey, we find that demographic profiles improve value alignment accuracy for most models, but at a systematic cost to individuality. That is, models pull responses toward demographic group centroids rather than preserving individual differences, a behavioral pattern we term alignment by stereotyping. Permutation tests (10,000 permutations, six demographic attributes, seven models) certify that top-performing models compress individuals far above the human baseline; within-family scaling amplifies this tradeoff while degrading intrinsic cultural understanding. Using a synthetic dialogue dataset validated on real human-chatbot conversations from PRISM (Kirk et al., 2024), we further show that distributing demographic signals across conversational turns partially suppresses prototype retrieval compared to compact demographic labels, a finding validated on real conversations via PRISM but requiring replication at larger scale.

2025

Real-time identification of out-of-context outputs from large language models (LLMs) is crucial for enterprises to safely adopt retrieval augmented generation (RAG) systems. In this work, we develop lightweight models capable of detecting when LLM-generated text deviates from retrieved source documents semantically. We compare their performance against open-source alternatives on data from credit policy and sustainability reports used in the banking industry. The fine-tuned DeBERTa model stands out for its superior performance, speed, and simplicity, as it requires no additional preprocessing or feature engineering. While recent research often prioritises state-of-the-art accuracy through fine-tuned generative LLMs and complex training pipelines, we demonstrate how detection models are deployed efficiently with high speed and minimal resource usage.