Quantity vs. Quality of Monolingual Source Data in Automatic Text Translation: Can It Be Too Little If It Is Too Good?
This addresses a practical issue for researchers and practitioners in machine translation, particularly in low-resource settings, but is incremental as it builds on prior work on data selection.
The study tackled the problem of determining the optimal quantity and quality of monolingual source data for low-resource neural machine translation, finding that selectively using high-quality or domain-relevant data often improves performance compared to using all available data.
Monolingual data, being readily available in large quantities, has been used to upscale the scarcely available parallel data to train better models for automatic translation. Self-learning, where a model is made to learn from its output, is one approach to exploit such data. However, it has been shown that too much of this data can be detrimental to the performance of the model if the available parallel data is comparatively extremely low. In this study, we investigate whether the monolingual data can also be too little and if this reduction, based on quality, has any effect on the performance of the translation model. Experiments have shown that on English-German low-resource NMT, it is often better to select only the most useful additional data, based on quality or closeness to the domain of the test data, than utilizing all of the available data.