One model, two languages: training bilingual parsers with harmonized treebanks
This addresses the need for efficient multilingual parsing, particularly for code-switching scenarios, though it appears incremental as it builds on existing treebanks and parsers.
The paper tackles the problem of training parsers that can handle multiple languages or code-switching by merging harmonized treebanks, resulting in bilingual parsers that often preserve or even improve accuracy compared to monolingual ones.
We introduce an approach to train lexicalized parsers using bilingual corpora obtained by merging harmonized treebanks of different languages, producing parsers that can analyze sentences in either of the learned languages, or even sentences that mix both. We test the approach on the Universal Dependency Treebanks, training with MaltParser and MaltOptimizer. The results show that these bilingual parsers are more than competitive, as most combinations not only preserve accuracy, but some even achieve significant improvements over the corresponding monolingual parsers. Preliminary experiments also show the approach to be promising on texts with code-switching and when more languages are added.