Wang, Zhiyuan, Jinhao Duan, Qingni Wang, Xiaofeng Zhu, Tianlong Chen, Xiaoshuang Shi, and Kaidi Xu. “COIN: Uncertainty-Guarding Selective Question Answering for Foundation Models With Provable Risk Guarantees”. Proceedings of the AAAI Conference on Artificial Intelligence 40, no. 40 (March 14, 2026): 33764–33772. Accessed May 25, 2026. https://ojs.aaai.org/index.php/AAAI/article/view/40667.