Dimitris Papailiopoulos


2023

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Prompted LLMs as Chatbot Modules for Long Open-domain Conversation
Gibbeum Lee | Volker Hartmann | Jongho Park | Dimitris Papailiopoulos | Kangwook Lee
Findings of the Association for Computational Linguistics: ACL 2023

In this paper, we propose MPC (Modular Prompted Chatbot), a new approach for creating high-quality conversational agents without the need for fine-tuning. Our method utilizes pre-trained large language models (LLMs) as individual modules for long-term consistency and flexibility, by using techniques such as few-shot prompting, chain-of-thought (CoT), and external memory. Our human evaluation results show that MPC is on par with fine-tuned chatbot models in open-domain conversations, making it an effective solution for creating consistent and engaging chatbots.

2022

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Utilizing Language-Image Pretraining for Efficient and Robust Bilingual Word Alignment
Tuan Dinh | Jy-yong Sohn | Shashank Rajput | Timothy Ossowski | Yifei Ming | Junjie Hu | Dimitris Papailiopoulos | Kangwook Lee
Findings of the Association for Computational Linguistics: EMNLP 2022

Word translation without parallel corpora has become feasible, rivaling the performance of supervised methods. Recent findings have shown the improvement in accuracy and robustness of unsupervised word translation (UWT) by utilizing visual observations, which are universal representations across languages.Our work investigates the potential of using not only visual observations but also pretrained language-image models for enabling a more efficient and robust UWT. We develop a novel UWT method dubbed Word Alignment using Language-Image Pretraining (WALIP), leveraging visual observations via the shared image-text embedding space of CLIPs (Radford et al., 2021). WALIP has a two-step procedure. First, we retrieve word pairs with high confidences of similarity, computed using our proposed image-based fingerprints, which define the initial pivot for the alignment.Second, we apply our robust Procrustes algorithm to estimate the linear mapping between two embedding spaces, which iteratively corrects and refines the estimated alignment.Our extensive experiments show that WALIP improves upon the state-of-the-art performance of bilingual word alignment for a few language pairs across different word embeddings and displays great robustness to the dissimilarity of language pairs or training corpora for two word embeddings.