Zheng Zhang

The rapid advancement of large language models (LLMs) has driven the deployment of LLM-based AI tutors on online learning platforms. This widespread adoption highlights an urgent need for systematic benchmarks to evaluate their tutoring capabilities. However, existing evaluations predominantly fo...

Large language models (LLMs) have achieved remarkable performance across diverse tasks, largely driven by large-scale pretraining. However, this data abundance introduces test data contamination, where benchmark datasets overlap with pretraining corpora, undermining the reliability of model evalu...

Large language models (LLMs) have achieved remarkable performance across a wide range of natural language processing (NLP) tasks. However, they remain susceptible to backdoor attacks, where adversaries embed hidden triggers in the input to induce malicious, attacker-specified behaviors. While exi...