I am a faculty member in computer and cognitive sciences at the University of Toronto. My research explores the intersection of language, cognition and computation.
Natural language utilizes a finite vocabulary to express an infinite array of ideas. I investigate how we adapt the lexicon to convey emerging meanings spontaneously or over longer time periods. In particular, I have been studying how words extend or combine to derive new meanings and the extent to which computational models can replicate these processes to construct and interpret novel word meanings.
In a related line of work, I have been involved in projects that examine crosslinguistic structures. I also develop computational methods for exploring the relations of language with other domains such as morality.
Lexicon development and evolution
- Fishkin, M., Chang, S., and Xu, Y. (2025) From Human child to Grey Parrot: Exploring a common model of word meaning extension across species. Cognitive Science, 49(10), e70129.
- Yu, L. and Xu, Y. (2025) Infinite mixture chaining: An efficiency-based framework for the dynamic construction of word meaning. Open Mind, 9, 1-24.
- Xu, A., Kemp, C., Frermann, L., and Xu, Y. (2024) Word reuse and combination support efficient communication of emerging concepts. PNAS, 121(46), e2406971121.
- Ramezani, A., Stellar, J.E., Feinberg, M., and Xu, Y. (2024) Evolution of the moral lexicon. Open Mind, 8, 1153-1169.
- Brochhagen, T., Boleda, G., Gualdoni, E., and Xu, Y. (2023) From language development to language evolution: A unified view of human lexical creativity. Science, 381(6656), 431-436.
- Xu, A., Stellar, J.E., and Xu, Y. (2021) Evolution of emotion semantics. Cognition, 217, 104875.
- Sun, Z., Zemel, R., and Xu, Y. (2021) A computational framework for slang generation. TACL, 9, 462-478.
- Ferreira Pinto Jr., R. and Xu, Y. (2021) A computational theory of child overextension. Cognition, 206, 104472.
- Habibi, A.A., Kemp, C., and Xu, Y. (2020) Chaining and the growth of linguistic categories. Cognition, 202, 104323.
- Ramiro, C., Srinivasan, M., Malt, B.C., and Xu, Y. (2018) Algorithms in the historical emergence of word senses. PNAS, 115(10), 2323-2328.
- Xu, Y., Malt, B.C. and Srinivasan, M. (2017) Evolution of word meanings through metaphorical mapping: Systematicity over the past millennium. Cognitive Psychology, 96, 41-53.
- Xu, Y., Regier, T. and Malt, B.C. (2016) Historical semantic chaining and efficient communication: The case of container names. Cognitive Science, 40(8):2081-2094.
Crosslinguistic structures
- Fugikawa, O., Hayman, O., Liu, R., Yu, L., Brochhagen, T., and Xu, Y. (2023) A computational analysis of crosslinguistic regularity in semantic change. Frontiers in Communication, 8:1136338.
- Hahn, M. and Xu, Y. (2022) Crosslinguistic word order variation reflects evolutionary pressures of dependency and information locality. PNAS, 119(24), e2122604119.
- Xu, Y., Duong, K., Malt, B.C., Jiang, S., and Srinivasan, M. (2020) Conceptual relations predict colexification across languages. Cognition, 201, 104280.
- Xu, Y., Liu, E., and Regier, T. (2020) Numeral systems across languages support efficient communication: From approximate numerosity to recursion. Open Mind, 4, 57-70.
- Kemp, C., Xu, Y., and Regier, T. (2018) Semantic typology and efficient communication. Annual Review of Linguistics, 4:109-128.
- Ramezani, A. and Xu, Y. (2025) Moral association graph: A cognitive model for automated moral inference. Topics in Cognitive Science, 17, 120-138.
- Ramezani, A., Liu, E., Lee, S.W.S., and Xu, Y. (2024) Quantifying the emergence of moral foundational lexicon in child language development. PNAS Nexus, 3(8), 278.
- Ramezani, A. and Xu, Y. (2023) Knowledge of cultural moral norms in large language models. In ACL.
- Xie, J.Y., Ferreira Pinto Jr., R., Hirst, G., and Xu, Y. (2019) Text-based inference of moral sentiment change. In EMNLP-IJCNLP.