Characterizing Out-of-Distribution Error via Optimal Transport - Lu, Yuzhe; Qin, Yilong; Zhai, Runtian; Shen, Andrew; Chen, Ketong; Wang, Zhenlin; Kolouri, Soheil; Stepputtis, Simon; Campbell, Joseph; Sycara, Katia (Advances in Neural Information Processing Systems, 2023)