Yifei Song
Author directory2026
Cross-Domain, Multi-Task Data-to-Text Generation without In-Domain Training Data
Yifei Song | Kun Efimov-Zhang | Claire Gardent
Findings of the Association for Computational Linguistics: EMNLP 2026
Yifei Song | Kun Efimov-Zhang | Claire Gardent
Findings of the Association for Computational Linguistics: EMNLP 2026
Structured data exists in many forms (tables, knowledge graphs, charts, and time series), and converting it into text may involve different generation tasks. However, most prior work on data-to-text (D2T) generation has focused on specific tasks and datasets, relying either on task-specific training data or on the zero-shot capabilities of large language models. We study cross-domain D2T generation in a setting where neither in-domain training text nor test references are available, and where domains, generation goals, and input structures vary substantially. We compare data-driven knowledge distillation (DDKD) against zero-shot inference and fine-tuning on out-of-domain D2T data, and introduce structure-preserving augmentation via structural subsampling and perturbation. Experiments on five benchmarks show that, at constant model size (1.7B parameters), DDKD consistently outperforms both fine-tuning and zero-shot inference. Moreover, the resulting small models outperform a much larger finetuned model on two of the five domains, achieving comparable performance on the remaining three. We further construct QUINTD-5, a fivefold extension of QUINTD-1, and show that simply scaling real target-domain inputs yields only modest gains, whereas our augmentation strategy remains more effective and more cost-efficient for cross-domain distillation.
Cross-lingual Biography Enrichment via Claim Extraction and Alignment
Yifei Song | Ziyang Chen | Emil Sayilov | Claire Gardent
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Yifei Song | Ziyang Chen | Emil Sayilov | Claire Gardent
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
English Wikipedia is often treated as the default encyclopedic source, yet non-English Wikipedia editions can contain richer locally grounded information for long-tail figures. We study cross-lingual biography enrichment: enriching an existing English biography with facts supported by a non-English biography about the same person. Focusing on women from non-English-speaking contexts, we introduce CLAW-4L, a benchmark consisting of 300 Wikipedia biography pairs linking an English biography with its French, Chinese or Azerbaijani counterpart, along with claim annotations and a fine-grained claim-pair relation corpus. We propose a claim-based enrichment framework that extracts English claims from both biographies, aligns them to identify enrichment evidence from the non-English biography, and rewrites the English biography using the selected claims. Our results show that non-English Wikipedia biographies provide valuable evidence for improving English biography coverage, while lower-resource settings remain challenging.
XQDT: eXplainable and Quantitative Data-Text Alignment Metric with Feedback Signals
Kun Efimov-Zhang | Yifei Song | Claire Gardent
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Kun Efimov-Zhang | Yifei Song | Claire Gardent
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Evaluating data-text alignment remains challenging: existing metrics often provide limited explanations for the scores, while prompt-based LLM-as-Judge methods can be expensive and unreliable. We present an end-to-end explainable evaluation metric that fine-tunes a language model to identify omitted, extra, incorrect, and correct data units in a data-text pair. These local judgements are aggregated into precision, recall, and F1 scores, providing both fine-grained diagnostic feedback and an interpretable measure of alignment quality. Across benchmarks, our fine-tuned models outperform LLM-as-Judge methods in error prediction and achieve competitive precision, recall, and F1 scores, while maintaining strong correlation with human judgements. Beyond evaluation, our verifier outputs also provide useful feedback signals for downstream correction and refinement, supporting alignment-oriented improvement of data-to-text and text-to-data. Code and resources are available at https://github.com/guihuzhang/xqdt.
2025
Multilingual Verbalisation of Knowledge Graphs
Yifei Song | William Soto Martinez | Anna Nikiforovskaya | Evan Chapple | Claire Gardent
Findings of the Association for Computational Linguistics: EMNLP 2025
Yifei Song | William Soto Martinez | Anna Nikiforovskaya | Evan Chapple | Claire Gardent
Findings of the Association for Computational Linguistics: EMNLP 2025
Most work on Knowledge Graph (KG) verbalisation is monolingual leaving open the question of how to scale KG-to-Text generation to languages with varying amounts of resources. In this work, we explore KG-to-Text generation on nine languages including five high-resource (HR) languages (English, Chinese, French, Spanish, Russian) and four low-resource (LR) languages (Breton, Irish, Maltese, Welsh). We first construct silver multilingual training data for all nine languages and new gold out-of-domain test data for the five HR languages. Using this data and already available in-domain test sets for 7 of our 9 languages, we then compare three strategies: (1) NLG+MT—a state-of-the-art KG-to-English model followed by Machine Translation (MT) into the target language; (2) FTMT—multilingual MT models fine-tuned end-to-end on the silver data; and (3) FewShot—few-shot LLM prompting comparing 4 LLMs. We explore different prompting strategies and show that our best prompting strategy performs the best on all 9 languages, discussing the relative performance of the three approaches on Low vs High Resource languages and on in- vs out-of-domain data.The models, the test set, and the silver training data are available at https://github.com/MeloS7/Multilingual-KG-Verbalisation.
MuCAL: Contrastive Alignment for Preference-Driven KG-to-Text Generation
Yifei Song | Claire Gardent
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Yifei Song | Claire Gardent
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
We propose MuCAL (Multilingual Contrastive Alignment Learning) to tackle the challenge of Knowledge Graphs (KG)-to-Text generation using preference learning, where reliable preference data is scarce. MuCAL is a multilingual KG/Text alignment model achieving robust cross-modal retrieval across multiple languages and difficulty levels. Building on MuCAL, we automatically create preference data by ranking candidate texts from three LLMs (Qwen2.5, DeepSeek-v3, Llama-3). We then apply Direct Preference Optimization (DPO) on these preference data, bypassing typical reward modelling steps to directly align generation outputs with graph semantics. Extensive experiments on KG-to-English Text generation show two main advantages: (1) Our KG/text similarity models provide a better signal for DPO than similar existing metrics, and (2) significantly better generalisation on out-of-domain datasets compared to standard instruction tuning. Our results highlight MuCAL’s effectiveness in supporting preference learning for KG-to-English Text generation and lay the foundation for future multilingual extensions. Code and data are available at https://github.com/MeloS7/MuCAL_DPO/tree/main.