Emma Hart


2024

pdf bib
An Open Intent Discovery Evaluation Framework
Grant Anderson | Emma Hart | Dimitra Gkatzia | Ian Beaver
Proceedings of the 25th Annual Meeting of the Special Interest Group on Discourse and Dialogue

In the development of dialog systems the discovery of the set of target intents to identify is a crucial first step that is often overlooked. Most intent detection works assume that a labelled dataset already exists, however creating these datasets is no trivial task and usually requires humans to manually analyse, decide on intent labels and tag accordingly. The field of Open Intent Discovery addresses this problem by automating the process of grouping utterances and providing the user with the discovered intents. Our Open Intent Discovery framework allows for the user to choose from a range of different techniques for each step in the discovery process, including the ability to extend previous works with a human-readable label generation stage. We also provide an analysis of the relationship between dataset features and optimal combination of techniques for each step to help others choose without having to explore every possible combination for their unlabelled data.

2020

pdf bib
Improving the Naturalness and Diversity of Referring Expression Generation models using Minimum Risk Training
Nikolaos Panagiaris | Emma Hart | Dimitra Gkatzia
Proceedings of the 13th International Conference on Natural Language Generation

In this paper we consider the problem of optimizing neural Referring Expression Generation (REG) models with sequence level objectives. Recently reinforcement learning (RL) techniques have been adopted to train deep end-to-end systems to directly optimize sequence-level objectives. However, there are two issues associated with RL training: (1) effectively applying RL is challenging, and (2) the generated sentences lack in diversity and naturalness due to deficiencies in the generated word distribution, smaller vocabulary size, and repetitiveness of frequent words and phrases. To alleviate these issues, we propose a novel strategy for training REG models, using minimum risk training (MRT) with maximum likelihood estimation (MLE) and we show that our approach outperforms RL w.r.t naturalness and diversity of the output. Specifically, our approach achieves an increase in CIDEr scores between 23%-57% in two datasets. We further demonstrate the robustness of the proposed method through a detailed comparison with different REG models.