A Latent Variable Model Approach to PMI-based Word Embeddings
Sanjeev Arora, Yuanzhi Li, Yingyu Liang, Tengyu Ma, Andrej Risteski
Abstract
Semantic word embeddings represent the meaning of a word via a vector, and are created by diverse methods. Many use nonlinear operations on co-occurrence statistics, and have hand-tuned hyperparameters and reweighting methods. This paper proposes a new generative model, a dynamic version of the log-linear topic model of Mnih and Hinton (2007). The methodological novelty is to use the prior to compute closed form expressions for word statistics. This provides a theoretical justification for nonlinear models like PMI, word2vec, and GloVe, as well as some hyperparameter choices. It also helps explain why low-dimensional semantic embeddings contain linear algebraic structure that allows solution of word analogies, as shown by Mikolov et al. (2013a) and many subsequent papers. Experimental support is provided for the generative model assumptions, the most important of which is that latent word vectors are fairly uniformly dispersed in space.- Anthology ID:
- Q16-1028
- Volume:
- Transactions of the Association for Computational Linguistics, Volume 4
- Month:
- Year:
- 2016
- Address:
- Cambridge, MA
- Editors:
- Lillian Lee, Mark Johnson, Kristina Toutanova
- Venue:
- TACL
- SIG:
- Publisher:
- MIT Press
- Note:
- Pages:
- 385–399
- Language:
- URL:
- https://aclanthology.org/Q16-1028
- DOI:
- 10.1162/tacl_a_00106
- Cite (ACL):
- Sanjeev Arora, Yuanzhi Li, Yingyu Liang, Tengyu Ma, and Andrej Risteski. 2016. A Latent Variable Model Approach to PMI-based Word Embeddings. Transactions of the Association for Computational Linguistics, 4:385–399.
- Cite (Informal):
- A Latent Variable Model Approach to PMI-based Word Embeddings (Arora et al., TACL 2016)
- PDF:
- https://preview.aclanthology.org/naacl24-info/Q16-1028.pdf
- Code
- PrincetonML/SemanticVector + additional community code