在与用户进行交流时，以任务为导向的对话系统必须根据对话历史记录在每个回合时跟踪用户的需求。这个称为对话状态跟踪（DST）的过程至关重要，因为它直接告知下游对话政策。近年来，DST引起了很大的兴趣，文本到文本范式作为受欢迎的方法。在本评论论文中，我们首先介绍任务及其相关的数据集。然后，考虑到最近出版的大量出版物，我们确定了2021 - 2022年研究的重点和研究进展。尽管神经方法已经取得了重大进展，但我们认为对话系统（例如概括性）的某些关键方面仍未得到充实。为了激励未来的研究，我们提出了几种研究途径。

针对任务导向的对话系统的强大状态跟踪目前仍然限于一些流行语言。本文显示，给定以一种语言设置的大规模对话数据，我们可以使用机器翻译自动为其他语言生成有效的语义解析器。我们提出了对话数据集的自动翻译，并进行对齐，以确保插槽值的忠实翻译，并消除以前的基准中使用的昂贵人类监督。我们还提出了一种新的上下文语义解析模型，它编码正式的插槽和值，只有最后一个代理和用户话语。我们表明，简洁的表示降低了翻译误差的复合效果，而不会损害实践中的准确性。我们评估我们对几个对话状态跟踪基准的方法。在Risawoz，Crosswoz，Crosswoz-Zh和Multiwoz-Zh Datasets，我们将最先进的技术提高11％，17％，20％和0.3％，以共同的目标准确度。我们为所有三个数据集提供了全面的错误分析，显示错误注释可以模糊模型质量的判断。最后，我们使用推荐方法创建了Risawoz英语和德语数据集。在这些数据集中，准确性在原始的11％以内，表示可能的高精度多语言对话数据集，而无需依赖昂贵的人类注释。

Virtual assistants such as Google Assistant, Alexa and Siri provide a conversational interface to a large number of services and APIs spanning multiple domains. Such systems need to support an ever-increasing number of services with possibly overlapping functionality. Furthermore, some of these services have little to no training data available. Existing public datasets for task-oriented dialogue do not sufficiently capture these challenges since they cover few domains and assume a single static ontology per domain. In this work, we introduce the the Schema-Guided Dialogue (SGD) dataset, containing over 16k multi-domain conversations spanning 16 domains. Our dataset exceeds the existing task-oriented dialogue corpora in scale, while also highlighting the challenges associated with building large-scale virtual assistants. It provides a challenging testbed for a number of tasks including language understanding, slot filling, dialogue state tracking and response generation. Along the same lines, we present a schema-guided paradigm for task-oriented dialogue, in which predictions are made over a dynamic set of intents and slots, provided as input, using their natural language descriptions. This allows a single dialogue system to easily support a large number of services and facilitates simple integration of new services without requiring additional training data. Building upon the proposed paradigm, we release a model for dialogue state tracking capable of zero-shot generalization to new APIs, while remaining competitive in the regular setting.

Even though machine learning has become the major scene in dialogue research community, the real breakthrough has been blocked by the scale of data available. To address this fundamental obstacle, we introduce the Multi-Domain Wizard-of-Oz dataset (MultiWOZ), a fully-labeled collection of human-human written conversations spanning over multiple domains and topics. At a size of 10k dialogues, it is at least one order of magnitude larger than all previous annotated task-oriented corpora. The contribution of this work apart from the open-sourced dataset labelled with dialogue belief states and dialogue actions is two-fold: firstly, a detailed description of the data collection procedure along with a summary of data structure and analysis is provided. The proposed data-collection pipeline is entirely based on crowd-sourcing without the need of hiring professional annotators; secondly, a set of benchmark results of belief tracking, dialogue act and response generation is reported, which shows the usability of the data and sets a baseline for future studies.

Dialogue State Tracking (DST), a key component of task-oriented conversation systems, represents user intentions by determining the values of pre-defined slots in an ongoing dialogue. Existing approaches use hand-crafted templates and additional slot information to fine-tune and prompt large pre-trained language models and elicit slot values from the dialogue context. Significant manual effort and domain knowledge is required to design effective prompts, limiting the generalizability of these approaches to new domains and tasks. In this work, we propose DiSTRICT, a generalizable in-context tuning approach for DST that retrieves highly relevant training examples for a given dialogue to fine-tune the model without any hand-crafted templates. Experiments with the MultiWOZ benchmark datasets show that DiSTRICT outperforms existing approaches in various zero-shot and few-shot settings using a much smaller model, thereby providing an important advantage for real-world deployments that often have limited resource availability.

在过去的十年中，对对话系统的兴趣已经大大增长。从扩展过程中，也有兴趣开发和改进意图分类和插槽填充模型，这是两个组件，这些组件通常在以任务为导向的对话框系统中使用。此外，良好的评估基准对于帮助比较和分析结合此类模型的系统很重要。不幸的是，该领域的许多文献仅限于对相对较少的基准数据集的分析。为了促进针对任务的对话系统的更强大的分析，我们对意图分类和插槽填充任务进行了公开可用数据集的调查。我们分类每个数据集的重要特征，并就每个数据集的适用性，优势和劣势进行讨论。我们的目标是，这项调查有助于提高这些数据集的可访问性，我们希望它们能够在未来评估意图分类和填充插槽模型中用于以任务为导向的对话框系统。

Diverse data formats and ontologies of task-oriented dialogue (TOD) datasets hinder us from developing general dialogue models that perform well on many datasets and studying knowledge transfer between datasets. To address this issue, we present ConvLab-3, a flexible dialogue system toolkit based on a unified TOD data format. In ConvLab-3, different datasets are transformed into one unified format and loaded by models in the same way. As a result, the cost of adapting a new model or dataset is significantly reduced. Compared to the previous releases of ConvLab (Lee et al., 2019b; Zhu et al., 2020b), ConvLab-3 allows developing dialogue systems with much more datasets and enhances the utility of the reinforcement learning (RL) toolkit for dialogue policies. To showcase the use of ConvLab-3 and inspire future work, we present a comprehensive study with various settings. We show the benefit of pre-training on other datasets for few-shot fine-tuning and RL, and encourage evaluating policy with diverse user simulators.

与具有粗粒度信息的Crosswoz（中文）和多发性（英文）数据集相比，没有数据集，可以正确处理细粒度和分层级别信息。在本文中，我们在香港发布了一份粤语知识驱动的对话数据集（KDDRES），将多转谈话中的信息放在一个特定的餐厅。我们的语料库包含0.8k次谈话，它来自10家餐厅，提供不同地区的各种风格。除此之外，我们还设计了细粒度的插槽和意图，以更好地捕获语义信息。基准实验和数据统计分析显示了我们数据集的多样性和丰富的注释。我们认为，KDDRE的出版可以是当前对话数据集的必要补充，以及社会中小企业（中小企业）更适合和更有价值，如为每家餐馆建立定制的对话系统。语料库和基准模型是公开可用的。

最近，通过“向导”模拟游戏收集了一类以任务为导向的对话（TOD）数据集。但是，《巫师》数据实际上是模拟的数据，因此与现实生活中的对话根本不同，这些对话更加嘈杂和随意。最近，Seretod挑战赛是组织的，并发布了Mobilecs数据集，该数据集由来自中国移动的真实用户和客户服务人员之间的真实世界对话框组成。基于Mobilecs数据集，Seretod挑战具有两个任务，不仅评估了对话系统本身的构建，而且还检查了对话框成绩单中的信息提取，这对于建立TOD的知识库至关重要。本文主要介绍了Mobilecs数据集对这两项任务的基线研究。我们介绍了如何构建两个基线，遇到的问题以及结果。我们预计基线可以促进令人兴奋的未来研究，以建立针对现实生活任务的人类机器人对话系统。

文本到SQL引起了自然语言处理和数据库社区的关注，因为它能够将自然语言中的语义转换为SQL查询及其在构建自然语言接口到数据库系统中的实际应用。文本到SQL的主要挑战在于编码自然话语的含义，解码为SQL查询，并翻译这两种形式之间的语义。这些挑战已被最近的进步解决了不同的范围。但是，对于这项任务仍缺乏全面的调查。为此，我们回顾了有关数据集，方法和评估的文本到SQL的最新进展，并提供了这项系统的调查，解决了上述挑战并讨论潜在的未来方向。我们希望这项调查可以作为快速获取现有工作并激励未来的研究。

Natural Language Generation (NLG) has improved exponentially in recent years thanks to the development of sequence-to-sequence deep learning technologies such as Transformer-based language models. This advancement has led to more fluent and coherent NLG, leading to improved development in downstream tasks such as abstractive summarization, dialogue generation and data-to-text generation. However, it is also apparent that deep learning based generation is prone to hallucinate unintended text, which degrades the system performance and fails to meet user expectations in many real-world scenarios. To address this issue, many studies have been presented in measuring and mitigating hallucinated texts, but these have never been reviewed in a comprehensive manner before. In this survey, we thus provide a broad overview of the research progress and challenges in the hallucination problem in NLG. The survey is organized into two parts: (1) a general overview of metrics, mitigation methods, and future directions; and (2) an overview of task-specific research progress on hallucinations in the following downstream tasks, namely abstractive summarization, dialogue generation, generative question answering, data-to-text generation, machine translation, and visual-language generation. This survey serves to facilitate collaborative efforts among researchers in tackling the challenge of hallucinated texts in NLG.

Training dialogue systems often entails dealing with noisy training examples and unexpected user inputs. Despite their prevalence, there currently lacks an accurate survey of dialogue noise, nor is there a clear sense of the impact of each noise type on task performance. This paper addresses this gap by first constructing a taxonomy of noise encountered by dialogue systems. In addition, we run a series of experiments to show how different models behave when subjected to varying levels of noise and types of noise. Our results reveal that models are quite robust to label errors commonly tackled by existing denoising algorithms, but that performance suffers from dialogue-specific noise. Driven by these observations, we design a data cleaning algorithm specialized for conversational settings and apply it as a proof-of-concept for targeted dialogue denoising.

Task-oriented dialogue (TOD) systems are mainly based on the slot-filling-based TOD (SF-TOD) framework, in which dialogues are broken down into smaller, controllable units (i.e., slots) to fulfill a specific task. A series of approaches based on this framework achieved remarkable success on various TOD benchmarks. However, we argue that the current TOD benchmarks are limited to surrogate real-world scenarios and that the current TOD models are still a long way from unraveling the scenarios. In this position paper, we first identify current status and limitations of SF-TOD systems. After that, we explore the WebTOD framework, the alternative direction for building a scalable TOD system when a web/mobile interface is available. In WebTOD, the dialogue system learns how to understand the web/mobile interface that the human agent interacts with, powered by a large-scale language model.

将对话状态跟踪（DST）概括为新数据特别具有挑战性，因为在培训过程中对丰富和细粒度的监督非常依赖。样本稀疏性，分布转移以及新概念和主题的发生经常导致推理期间的严重降级。在本文中，我们提出了一种培训策略，以构建提取性DST模型，而无需精细颗粒的手动跨度标签。两种新型的输入级辍学方法减轻了样品稀疏性的负面影响。我们提出了一种具有统一编码器的新模型体系结构，该架构通过利用注意机制来支持价值和插槽独立性。我们结合了三复制策略DST的优势和价值匹配，以从互补的预测中受益，而无需违反本体独立性的原则。我们的实验表明，可以在没有手动跨度标签的情况下训练提取的DST模型。我们的体系结构和培训策略提高了对样本稀疏，新概念和主题的鲁棒性，从而在一系列基准中提高了最先进的表现。我们进一步强调了我们的模型有效地从非拨号数据中学习的能力。

用户模拟器（USS）通常用于通过增强学习训练面向任务的对话系统（DSS）。相互作用通常是在语义层面上以提高效率的，但是从语义动作到自然语言仍然存在差距，这会导致培训和部署环境之间的不匹配。在培训期间，将自然语言生成（NLG）模块与USS结合在一起可以部分解决此问题。但是，由于US的策略和NLG是单独优化的，因此在给定的情况下，这些模拟的用户话语可能不够自然。在这项工作中，我们提出了一个基于生成变压器的用户模拟器（Gentus）。 Gentus由编码器结构组成，这意味着它可以共同优化用户策略和自然语言。 Gentus既产生语义动作又产生自然语言话语，从而保留了解释性和增强语言的变化。另外，通过将输入和输出表示为单词序列以及使用大型的预训练语言模型，我们可以在功能表示中实现普遍性。我们通过自动指标和人类评估评估绅士。我们的结果表明，绅士会产生更多的自然语言，并能够以零拍的方式转移到看不见的本体论中。此外，通过加强学习为培训专业用户模拟器打开大门，可以进一步塑造其行为。

最近延伸预留下芬特的神经模型的神经模型继续实现新的最新导致对话状态跟踪（DST）基准的联合目标准确性（JGA）。但是，我们调查了他们的稳健性，因为它们在JGA中显示了急剧下降，以便与现实扰动的话语或对话框流动的对话。通过清单（Ribeiro等，2020），我们设计了一个名为CheckDST的度量集合，促进DST模型的比较，通过测试具有增强测试集的众所周知的弱点来促进革命性的全面尺寸。我们使用CheckDST评估最近的DST模型，并认为模型应该更全面地评估，而不是在JGA上追求最先进的JGA，因为更高的JGA不保证更好的整体稳健性。我们发现基于跨度的分类模型是有弹性的，不合适的命名实体，但对语言品种不强大，而那些基于自回归语言模型的人概括为语言变化，但往往会记住命名实体并往往是幻觉。由于它们各自的弱点，两种方法都不适合现实世界部署。我们认为CheckDst是未来研究的一个有用指南，用于开发面向任务的对话模型，体现了各种方法的优势。

本文介绍了端到端以任务为导向的对话（TOD）的本体学预验证的语言模型（OPAL）。与Chit-Chat对话模型不同，面向任务的对话模型至少满足两个特定于任务的模块：对话状态跟踪器（DST）和响应生成器（RG）。对话状态由域插槽值三元组成，它们被认为是用户搜索与域相关数据库的约束。带有带注释的对话状态的大规模面向任务的对话数据通常是无法访问的。它可以防止针对任务对话的审慎语言模型的开发。我们提出了一种简单而有效的预处理方法来减轻此问题，该方法由两个预审进阶段组成。第一阶段是在大规模上下文文本数据上预处理，其中文本的结构化信息是由信息提取工具提取的。为了弥合训练方法和下游任务之间的差距，我们设计了两个预训练的任务：类似于本体的三重恢复和下一文本生成，分别模拟了DST和RG。第二阶段是在TOD数据上微调验证的模型。实验结果表明，即使没有CAMREST676和MULTIWOZ基准的任何TOD数据，我们提出的方法即使没有任何TOD数据，我们提出的方法也可以提高竞争性能。

如何有效地构建和使用对话数据，以及如何在不同域中在不同域中部署模型可能是建立面向任务的对话系统的两个关键问题。在本文中，我们提出了一种新颖的手动指导对话方案，以减轻这些问题，在该方案中，代理商从对话和手册中学习任务。该手册是一个非结构化的文本文档，可指导代理在对话过程中与用户和数据库进行交互。我们提出的方案降低了对话模型对细粒领域本体的依赖性，并使它们更灵活以适应各种领域。然后，我们为完全注销的多域数据集Magdial贡献以支持我们的方案。它介绍了三个对话建模子任务：指令匹配，参数填充和响应生成。对这些子任务进行建模与人类代理的行为模式一致。实验表明，手动引导对话方案提高了构建对话系统中的数据效率和域可伸缩性。数据集和基准将公开用于促进未来的研究。

Controllable Text Generation (CTG) is emerging area in the field of natural language generation (NLG). It is regarded as crucial for the development of advanced text generation technologies that are more natural and better meet the specific constraints in practical applications. In recent years, methods using large-scale pre-trained language models (PLMs), in particular the widely used transformer-based PLMs, have become a new paradigm of NLG, allowing generation of more diverse and fluent text. However, due to the lower level of interpretability of deep neural networks, the controllability of these methods need to be guaranteed. To this end, controllable text generation using transformer-based PLMs has become a rapidly growing yet challenging new research hotspot. A diverse range of approaches have emerged in the recent 3-4 years, targeting different CTG tasks which may require different types of controlled constraints. In this paper, we present a systematic critical review on the common tasks, main approaches and evaluation methods in this area. Finally, we discuss the challenges that the field is facing, and put forward various promising future directions. To the best of our knowledge, this is the first survey paper to summarize CTG techniques from the perspective of PLMs. We hope it can help researchers in related fields to quickly track the academic frontier, providing them with a landscape of the area and a roadmap for future research.

以任务为导向的对话系统（TDSS）主要在离线设置或人类评估中评估。评估通常仅限于单转或非常耗时。作为替代方案，模拟用户行为的用户模拟器使我们能够考虑一组广泛的用户目标，以生成类似人类的对话以进行模拟评估。使用现有的用户模拟器来评估TDSS是具有挑战性的，因为用户模拟器主要旨在优化TDSS的对话策略，并且评估功能有限。此外，对用户模拟器的评估是一个开放的挑战。在这项工作中，我们提出了一个用于端到端TDS评估的隐喻用户模拟器，如果它在与系统的交互中模拟用户的类似思维，则定义模拟器是隐喻的。我们还提出了一个基于测试人员的评估框架，以生成变体，即具有不同功能的对话系统。我们的用户模拟器构建了一个隐喻的用户模型，该模型通过参考遇到新项目时的先验知识来帮助模拟器进行推理。我们通过检查模拟器与变体之间的模拟相互作用来估计模拟器的质量。我们的实验是使用三个TDS数据集进行的。与基于议程的模拟器和三个数据集上的SEQ2SEQ模型相比，隐喻用户模拟器与手动评估的一致性更好。我们的测试人员框架展示了效率，并且可以更好地概括和可扩展性，因为它可以适用于多个域中的对话和多个任务，例如对话建议和电子商务对话。