Saeed Najafi


2024

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RIFF: Learning to Rephrase Inputs for Few-shot Fine-tuning of Language Models
Saeed Najafi | Alona Fyshe
Findings of the Association for Computational Linguistics ACL 2024

Pre-trained Language Models (PLMs) can be accurately fine-tuned for downstream text processing tasks. Recently, researchers have introduced several parameter-efficient fine-tuning methods that optimize input prompts or adjust a small number of model parameters (e.g LoRA). In this study, we explore the impact of altering the input text of the original task in conjunction with parameter-efficient fine-tuning methods. To most effectively rewrite the input text, we train a few-shot paraphrase model with a Maximum-Marginal Likelihood objective. Using six few-shot text classification datasets, we show that enriching data with paraphrases at train and test time enhances the performance beyond what can be achieved with parameter-efficient fine-tuning alone. The code used for our experiments can be found at https://github.com/SaeedNajafi/RIFF.

2023

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Weakly-Supervised Questions for Zero-Shot Relation Extraction
Saeed Najafi | Alona Fyshe
Proceedings of the 17th Conference of the European Chapter of the Association for Computational Linguistics

Zero-Shot Relation Extraction (ZRE) is the task of Relation Extraction where the training and test sets have no shared relation types. This very challenging domain is a good test of a model’s ability to generalize. Previous approaches to ZRE reframed relation extraction as Question Answering (QA), allowing for the use of pre-trained QA models. However, this method required manually creating gold question templates for each new relation. Here, we do away with these gold templates and instead learn a model that can generate questions for unseen relations. Our technique can successfully translate relation descriptions into relevant questions, which are then leveraged to generate the correct tail entity. On tail entity extraction, we outperform the previous state-of-the-art by more than 16 F1 points without using gold question templates. On the RE-QA dataset where no previous baseline for relation extraction exists, our proposed algorithm comes within 0.7 F1 points of a system that uses gold question templates. Our model also outperforms the state-of-the-art ZRE baselines on the FewRel and WikiZSL datasets, showing that QA models no longer need template questions to match the performance of models specifically tailored to the ZRE task. Our implementation is available at https://github.com/fyshelab/QA-ZRE.

2018

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Comparison of Assorted Models for Transliteration
Saeed Najafi | Bradley Hauer | Rashed Rubby Riyadh | Leyuan Yu | Grzegorz Kondrak
Proceedings of the Seventh Named Entities Workshop

We report the results of our experiments in the context of the NEWS 2018 Shared Task on Transliteration. We focus on the comparison of several diverse systems, including three neural MT models. A combination of discriminative, generative, and neural models obtains the best results on the development sets. We also put forward ideas for improving the shared task.

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String Transduction with Target Language Models and Insertion Handling
Garrett Nicolai | Saeed Najafi | Grzegorz Kondrak
Proceedings of the Fifteenth Workshop on Computational Research in Phonetics, Phonology, and Morphology

Many character-level tasks can be framed as sequence-to-sequence transduction, where the target is a word from a natural language. We show that leveraging target language models derived from unannotated target corpora, combined with a precise alignment of the training data, yields state-of-the art results on cognate projection, inflection generation, and phoneme-to-grapheme conversion.

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Combining Neural and Non-Neural Methods for Low-Resource Morphological Reinflection
Saeed Najafi | Bradley Hauer | Rashed Rubby Riyadh | Leyuan Yu | Grzegorz Kondrak
Proceedings of the CoNLL–SIGMORPHON 2018 Shared Task: Universal Morphological Reinflection

2017

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If you can’t beat them, join them: the University of Alberta system description
Garrett Nicolai | Bradley Hauer | Mohammad Motallebi | Saeed Najafi | Grzegorz Kondrak
Proceedings of the CoNLL SIGMORPHON 2017 Shared Task: Universal Morphological Reinflection