# Bilingual Lexicon Induction with Semi-supervision in Non-Isometric Embedding Spaces

arXiv: https://arxiv.org/abs/1908.06625 · HTML: https://mlsanity.com/paper/1908.06625/

## Key facts

- Cited by 35 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 19 Aug 2019.

## Built on by (most cited first, 30 of 35)

- [MetaXL: Meta Representation Transformation for Low-resource Cross-lingual Learning](https://mlsanity.com/paper/2104.07908/) (2021)
- [Improving Word Translation via Two-Stage Contrastive Learning](https://mlsanity.com/paper/2203.08307/) (2022)
- [Crossing the Conversational Chasm: A Primer on Natural Language Processing for Multilingual Task-Oriented Dialogue Systems](https://mlsanity.com/paper/2104.08570/) (2021)
- [Transfer to a Low-Resource Language via Close Relatives: The Case Study on Faroese](https://mlsanity.com/paper/2304.08823/) (2023)
- [Combining Static Word Embeddings and Contextual Representations for Bilingual Lexicon Induction](https://mlsanity.com/paper/2106.03084/) (2021)
- [Subword Mapping and Anchoring across Languages](https://mlsanity.com/paper/2109.04556/) (2021)
- [Meta-Learning a Cross-lingual Manifold for Semantic Parsing](https://mlsanity.com/paper/2209.12577/) (2022)
- [Unsupervised Multilingual Sentence Embeddings for Parallel Corpus Mining](https://mlsanity.com/paper/2105.10419/) (2021)
- [IsoVec: Controlling the Relative Isomorphism of Word Embedding Spaces](https://mlsanity.com/paper/2210.05098/) (2022)
- [Improving Bilingual Lexicon Induction with Cross-Encoder Reranking](https://mlsanity.com/paper/2210.16953/) (2022)
- [Bilingual Lexicon Induction for Low-Resource Languages using Graph Matching via Optimal Transport](https://mlsanity.com/paper/2210.14378/) (2022)
- [Self-Augmented In-Context Learning for Unsupervised Word Translation](https://mlsanity.com/paper/2402.10024/) (2024)
- [The Shape of Word Embeddings: Quantifying Non-Isometry With Topological Data Analysis](https://mlsanity.com/paper/2404.00500/) (2024)
- [RAPO: An Adaptive Ranking Paradigm for Bilingual Lexicon Induction](https://mlsanity.com/paper/2210.09926/) (2022)
- [When your Cousin has the Right Connections: Unsupervised Bilingual Lexicon Induction for Related Data-Imbalanced Languages](https://mlsanity.com/paper/2305.14012/) (2023)
- [Linear Cross-Lingual Mapping of Sentence Embeddings](https://mlsanity.com/paper/2305.14256/) (2023)
- [GRI: Graph-based Relative Isomorphism of Word Embedding Spaces](https://mlsanity.com/paper/2310.12360/) (2023)
- [GARI: Graph Attention for Relative Isomorphism of Arabic Word Embeddings](https://mlsanity.com/paper/2310.13068/) (2023)
- [Word Embedding Transformation for Robust Unsupervised Bilingual Lexicon Induction](https://mlsanity.com/paper/2105.12297/) (2021)
- [Learning a Reversible Embedding Mapping using Bi-Directional Manifold Alignment](https://mlsanity.com/paper/2107.00124/) (2021)
- [An Analysis of Euclidean vs. Graph-Based Framing for Bilingual Lexicon Induction from Word Embedding Spaces](https://mlsanity.com/paper/2109.12640/) (2021)
- [On Bilingual Lexicon Induction with Large Language Models](https://mlsanity.com/paper/2310.13995/) (2023)
- [ProMap: Effective Bilingual Lexicon Induction via Language Model Prompting](https://mlsanity.com/paper/2310.18778/) (2023)
- [LexGen: Domain-aware Multilingual Lexicon Generation](https://mlsanity.com/paper/2405.11200/) (2024)
- [Modular Sentence Encoders: Separating Language Specialization from Cross-Lingual Alignment](https://mlsanity.com/paper/2407.14878/) (2024)
- [Words as Bridges: Exploring Computational Support for Cross-Disciplinary Translation Work](https://mlsanity.com/paper/2503.18471/) (2025)
- [Isomorphic Cross-lingual Embeddings for Low-Resource Languages](https://mlsanity.com/paper/2203.14632/) (2022)
- [Multilingual Word Embeddings for Low-Resource Languages using Anchors and a Chain of Related Languages](https://mlsanity.com/paper/2311.12489/) (2023)
- [TokAlign++: Advancing Vocabulary Adaptation via Better Token Alignment](https://mlsanity.com/paper/2605.13429/) (2026)
- [Embedding-Enhanced Giza++: Improving Alignment in Low- and High- Resource Scenarios Using Embedding Space Geometry](https://mlsanity.com/paper/2104.08721/) (2021)

## Abstract (arXiv)

Recent work on bilingual lexicon induction (BLI) has frequently depended either on aligned bilingual lexicons or on distribution matching, often with an assumption about the isometry of the two spaces. We propose a technique to quantitatively estimate this assumption of the isometry between two embedding spaces and empirically show that this assumption weakens as the languages in question become increasingly etymologically distant. We then propose Bilingual Lexicon Induction with Semi-Supervision (BLISS) --- a semi-supervised approach that relaxes the isometric assumption while leveraging both limited aligned bilingual lexicons and a larger set of unaligned word embeddings, as well as a novel hubness filtering technique. Our proposed method obtains state of the art results on 15 of 18 language pairs on the MUSE dataset, and does particularly well when the embedding spaces don't appear to be isometric. In addition, we also show that adding supervision stabilizes the learning procedure, and is effective even with minimal supervision.