• Backtranslation feedback improves user confidence in MT, not quality

      Zouhar, Vilém; Novák, Michal; Žilinec, Matúš; Bojar, Ondřej; Obregón, Mateo; Hill, Robin L; Blain, Frédéric; Fomicheva, Marina; Specia, Lucia; Yankovskaya, Lisa; et al. (Association for Computational Linguistics, 2021-06-01)
      Translating text into a language unknown to the text’s author, dubbed outbound translation, is a modern need for which the user experience has significant room for improvement, beyond the basic machine translation facility. We demonstrate this by showing three ways in which user confidence in the outbound translation, as well as its overall final quality, can be affected: backward translation, quality estimation (with alignment) and source paraphrasing. In this paper, we describe an experiment on outbound translation from English to Czech and Estonian. We examine the effects of each proposed feedback module and further focus on how the quality of machine translation systems influence these findings and the user perception of success. We show that backward translation feedback has a mixed effect on the whole process: it increases user confidence in the produced translation, but not the objective quality.
    • BERGAMOT-LATTE submissions for the WMT20 quality estimation shared task

      Fomicheva, Marina; Sun, Shuo; Yankovskaya, Lisa; Blain, Frédéric; Chaudhary, Vishrav; Fishel, Mark; Guzmán, Francisco; Specia, Lucia (Association for Computational Linguistics, 2020-11-30)
      This paper presents our submission to the WMT2020 Shared Task on Quality Estimation (QE). We participate in Task and Task 2 focusing on sentence-level prediction. We explore (a) a black-box approach to QE based on pre-trained representations; and (b) glass-box approaches that leverage various indicators that can be extracted from the neural MT systems. In addition to training a feature-based regression model using glass-box quality indicators, we also test whether they can be used to predict MT quality directly with no supervision. We assess our systems in a multi-lingual setting and show that both types of approaches generalise well across languages. Our black-box QE models tied for the winning submission in four out of seven language pairs inTask 1, thus demonstrating very strong performance. The glass-box approaches also performed competitively, representing a light-weight alternative to the neural-based models.
    • Unsupervised quality estimation for neural machine translation

      Fomicheva, Marina; Sun, Shuo; Yankovskaya, Lisa; Blain, Frédéric; Guzmán, Francisco; Fishel, Mark; Aletras, Nikolaos; Chaudhary, Vishrav; Specia, Lucia (Association for Computational Linguistics, 2020-09-01)
      Quality Estimation (QE) is an important component in making Machine Translation (MT) useful in real-world applications, as it is aimed to inform the user on the quality of the MT output at test time. Existing approaches require large amounts of expert annotated data, computation and time for training. As an alternative, we devise an unsupervised approach to QE where no training or access to additional resources besides the MT system itself is required. Different from most of the current work that treats the MT system as a black box, we explore useful information that can be extracted from the MT system as a by-product of translation. By employing methods for uncertainty quantification, we achieve very good correlation with human judgments of quality, rivalling state-of-the-art supervised QE models. To evaluate our approach we collect the first dataset that enables work on both black-box and glass-box approaches to QE.