预先训练的模型已经证明是强大的增强面向任务的对话系统。但是，目前的预训练方法主要关注增强对话的理解和生成任务，同时忽略对话策略的开发。在本文中，我们提出了一个小说预先训练的对话模型，明确地通过半监督学习明确地从有限标记的对话框和大规模未标记的对话框中学习对话策略。具体而言，我们在预训练期间介绍一个对话框预测任务，以便在预训练中进行策略优化，并使用一致性正则化术语在未标记的对话的帮助下优化学习的表示。我们还实施了一个浇注机制来称量合适的未标记对话框样本。经验结果表明，星系大大提高了面向任务为导向的对话系统的性能，并在基准数据集中实现了新的最先进结果：车载，多种多纤2.0和多纺，改善其端到端合并分数2.5,5.3和5.5分。我们还显示Galaxy比各种低资源设置下的现有模型更强大的少量射击能力。

最近，培训预培训方法在以任务为导向的对话框（TOD）系统中表现出了很大的成功。但是，大多数现有的预培训模型用于TOD专注于对话的理解或对话生成，但并非两者兼而有之。在本文中，我们提出了Space-3，这是一种新型的统一的半监督预培训的预训练的对话模型，从大规模对话CORPORA中学习有限的注释，可以有效地对广泛的下游对话任务进行微调。具体而言，Space-3由单个变压器中的四个连续组件组成，以维护TOD系统中的任务流：（i）对话框编码模块编码对话框历史记录，（ii）对话框理解模块以从任一用户中提取语义向量查询或系统响应，（iii）一个对话框策略模块，以生成包含响应高级语义的策略向量，以及（iv）对话框生成模块以产生适当的响应。我们为每个组件设计一个专门的预训练目标。具体而言，我们预先培训对话框编码模块，使用跨度掩码语言建模，以学习上下文化对话框信息。为了捕获“结构化对话框”语义，我们通过额外的对话注释通过新颖的树诱导的半监视对比度学习目标来预先培训对话框理解模块。此外，我们通过将其输出策略向量与响应响应的语义向量之间的L2距离最小化以进行策略优化，从而预先培训对话策略模块。最后，对话框生成模型由语言建模预先训练。结果表明，Space-3在八个下游对话框基准中实现最新性能，包括意图预测，对话框状态跟踪和端到端对话框建模。我们还表明，在低资源设置下，Space-3比现有模型具有更强的射击能力。

具有对比性学习目标的预训练方法在对话了解任务中表现出了显着的成功。但是，当前的对比学习仅将自调查的对话样本视为正样本，并将所有其他对话样本视为负面样本，即使在语义上相关的对话框中，也会强制执行不同的表示。在本文中，我们提出了一个树木结构化的预培训对话模型Space-2，该模型从有限标记的对话框和大规模的无标记的对话框COLPORA通过半监督的对比度预培训来学习对话框表示。具体而言，我们首先定义一个通用的语义树结构（STS），以统一不同对话框数据集的注释模式，以便可以利用所有标记数据中存储的丰富结构信息。然后，我们提出了一个新颖的多视图分数功能，以增加共享类似STS的所有可能对话框的相关性，并且在监督的对比预训练期间仅推开其他完全不同的对话框。为了充分利用未标记的对话，还增加了基本的自我监督对比损失，以完善学习的表示。实验表明，我们的方法可以在DialogLue基准测试中实现新的最新结果，该基准由七个数据集和四个流行的对话框组成。为了获得可重复性，我们在https://github.com/alibabaresearch/damo-convai/tree/main/main/space-2上发布代码和数据。

通过利用未标记的对话框数据来开发半监督的面向任务的对话框（TOD）系统已吸引了越来越多的兴趣。对于对潜在状态TOD模型的半监督学习，经常使用变异学习，但遭受了通过离散潜在变量传播的梯度的令人讨厌的高度变化，以及间接优化目标对数的弊端。最近，一种称为关节随机近似（JSA）的替代算法已出现，用于学习具有令人印象深刻的性能的离散潜在可变模型。在本文中，我们建议将JSA应用于对潜在状态TOD模型的半监督学习，该模型称为JSA-TOD。据我们所知，JSA-TOD代表了开发基于JSA的半监督学习的第一批工作，用于对TOD系统（例如TOD系统）这样的长期顺序生成问题的离散潜在可变条件模型。广泛的实验表明，JSA-TOD明显优于其变异学习对应物。值得注意的是，使用20％标签的半监督JSA-TOD在Multiwoz2.1上的全面监督基线附近。

本文研究了以任务为导向的对话系统中的曝光偏差问题，其中模型在多个转弯中生成的内容驱动对话框上下文远离训练时间的地面真相分布，从而引入了错误传播并损害了TOD系统的稳健性。为了弥合训练和推理多转弯任务导向对话框之间的差距，我们建议会话级抽样，该采样将模型明确地暴露于培训期间对话框上下文的采样生成的内容。此外，我们采用基于辍学的一致性正规化与屏蔽策略R掩码，以进一步提高模型的鲁棒性和性能。拟议的UBARV2在标准化评估基准Multiwoz上实现了最先进的性能，并且广泛的实验显示了所提出的方法的有效性。

预先接受训练的语言模型的最新进展具有显着改善的神经反应生成。但是，现有方法通常将对话背景视为令牌的线性序列，并通过令牌级自我关注学习生成下一个单词。这些令牌级编码阻碍了话语中话语水平一致性的探索。本文介绍了对话贝特，这是一种新的会话响应生成模型，可以增强以前的基于PLM的对话模型。 DialogBert采用分层变压器架构。为了有效地捕捉话语中的话语水平一致性，我们提出了两种培训目标，包括蒙面的话语回归和分布式话语秩序与原始BERT训练相比。在三个多转对谈话数据集上的实验表明，在定量评估方面，我们的方法非常优于BART和Dialogpt等基线。人类评估表明，DialogBert比具有显着利润率的基线产生更加连贯，信息和人类的反应。

Recent advances in neural approaches greatly improve task-oriented dialogue (TOD) systems which assist users to accomplish their goals. However, such systems rely on costly manually labeled dialogs which are not available in practical scenarios. In this paper, we present our models for Track 2 of the SereTOD 2022 challenge, which is the first challenge of building semi-supervised and reinforced TOD systems on a large-scale real-world Chinese TOD dataset MobileCS. We build a knowledge-grounded dialog model to formulate dialog history and local KB as input and predict the system response. And we perform semi-supervised pre-training both on the labeled and unlabeled data. Our system achieves the first place both in the automatic evaluation and human interaction, especially with higher BLEU (+7.64) and Success (+13.6\%) than the second place.

End-to-end task bots are typically learned over a static and usually limited-size corpus. However, when deployed in dynamic, changing, and open environments to interact with users, task bots tend to fail when confronted with data that deviate from the training corpus, i.e., out-of-distribution samples. In this paper, we study the problem of automatically adapting task bots to changing environments by learning from human-bot interactions with minimum or zero human annotations. We propose SL-AGENT, a novel self-learning framework for building end-to-end task bots. SL-AGENT consists of a dialog model and a pre-trained reward model to predict the quality of an agent response. It enables task bots to automatically adapt to changing environments by learning from the unlabeled human-bot dialog logs accumulated after deployment via reinforcement learning with the incorporated reward model. Experimental results on four well-studied dialog tasks show the effectiveness of SL-AGENT to automatically adapt to changing environments, using both automatic and human evaluations. We will release code and data for further research.

Incorporating external knowledge into the response generation process is essential to building more helpful and reliable dialog agents. However, collecting knowledge-grounded conversations is often costly, calling for a better pre-trained model for grounded dialog generation that generalizes well w.r.t. different types of knowledge. In this work, we propose KPT (Keyword-guided Pre-Training), a novel self-supervised pre-training method for grounded dialog generation without relying on extra knowledge annotation. Specifically, we use a pre-trained language model to extract the most uncertain tokens in the dialog as keywords. With these keywords, we construct two kinds of knowledge and pre-train a knowledge-grounded response generation model, aiming at handling two different scenarios: (1) the knowledge should be faithfully grounded; (2) it can be selectively used. For the former, the grounding knowledge consists of keywords extracted from the response. For the latter, the grounding knowledge is additionally augmented with keywords extracted from other utterances in the same dialog. Since the knowledge is extracted from the dialog itself, KPT can be easily performed on a large volume and variety of dialogue data. We considered three data sources (open-domain, task-oriented, conversational QA) with a total of 2.5M dialogues. We conduct extensive experiments on various few-shot knowledge-grounded generation tasks, including grounding on dialog acts, knowledge graphs, persona descriptions, and Wikipedia passages. Our comprehensive experiments and analyses demonstrate that KPT consistently outperforms state-of-the-art methods on these tasks with diverse grounding knowledge.

我们提出了一种新颖的体系结构，用于使用离散的潜在变量对以任务为导向的对话进行解释建模，以表示对话动作。我们的模型基于变异复发性神经网络（VRNN），不需要明确的语义信息注释。与以前的作品不同，我们的方法模型系统和用户单独转动并执行数据库查询建模，这使该模型适用于以任务为导向的对话，同时生成易于解释的可解释的可解释的潜在变量。我们表明，我们的模型在三个数据集中的困惑和BLEU方面优于先前的方法，我们提出了一种衡量对话成功的方法，而无需专家注释。最后，我们提出了一种新颖的方式来解释有关系统动作的潜在变量语义。

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。

Interview has been regarded as one of the most crucial step for recruitment. To fully prepare for the interview with the recruiters, job seekers usually practice with mock interviews between each other. However, such a mock interview with peers is generally far away from the real interview experience: the mock interviewers are not guaranteed to be professional and are not likely to behave like a real interviewer. Due to the rapid growth of online recruitment in recent years, recruiters tend to have online interviews, which makes it possible to collect real interview data from real interviewers. In this paper, we propose a novel application named EZInterviewer, which aims to learn from the online interview data and provides mock interview services to the job seekers. The task is challenging in two ways: (1) the interview data are now available but still of low-resource; (2) to generate meaningful and relevant interview dialogs requires thorough understanding of both resumes and job descriptions. To address the low-resource challenge, EZInterviewer is trained on a very small set of interview dialogs. The key idea is to reduce the number of parameters that rely on interview dialogs by disentangling the knowledge selector and dialog generator so that most parameters can be trained with ungrounded dialogs as well as the resume data that are not low-resource. Evaluation results on a real-world job interview dialog dataset indicate that we achieve promising results to generate mock interviews. With the help of EZInterviewer, we hope to make mock interview practice become easier for job seekers.

As the functionality of dialogue systems evolves, hybrid dialogue systems that accomplish user-specific goals and participate in open-topic chitchat with users are attracting growing attention. Existing research learns both tasks concurrently utilizing a multi-task fusion technique but ignores the negative transfer phenomenon induced by the unique textual style differences. Therefore, contrastive learning based on the latent variable model is used to decouple the various textual genres in the latent space. We devise supervised and self-supervised positive and negative sample constructions for diverse datasets. In addition, to capitalize on the style information contained in the decoupled latent variables, we employ a style prefix that incorporates latent variables further to control the generation of responses with varying styles. We performed extensive experiments on three dialogue datasets, including a hybrid dialogue dataset and two task-oriented dialogue datasets. The experimental results demonstrate that our method can mitigate the negative style transfer issue and achieves state-of-the-art performance on multiple dialogue datasets.

Natural Language Generation (NLG) represents a large collection of tasks in the field of NLP. While many of these tasks have been tackled well by the cross-entropy (CE) loss, the task of dialog generation poses a few unique challenges for this loss function. First, CE loss assumes that for any given input, the only possible output is the one available as the ground truth in the training dataset. In general, this is not true for any task, as there can be multiple semantically equivalent sentences, each with a different surface form. This problem gets exaggerated further for the dialog generation task, as there can be multiple valid responses (for a given context) that not only have different surface forms but are also not semantically equivalent. Second, CE loss does not take the context into consideration while processing the response and, hence, it treats all ground truths with equal importance irrespective of the context. But, we may want our final agent to avoid certain classes of responses (e.g. bland, non-informative or biased responses) and give relatively higher weightage for more context-specific responses. To circumvent these shortcomings of the CE loss, in this paper, we propose a novel loss function, CORAL, that directly optimizes recently proposed estimates of human preference for generated responses. Using CORAL, we can train dialog generation models without assuming non-existence of response other than the ground-truth. Also, the CORAL loss is computed based on both the context and the response. Extensive comparisons on two benchmark datasets show that the proposed methods outperform strong state-of-the-art baseline models of different sizes.

Task-oriented dialog(TOD) aims to assist users in achieving specific goals through multi-turn conversation. Recently, good results have been obtained based on large pre-trained models. However, the labeled-data scarcity hinders the efficient development of TOD systems at scale. In this work, we constructed a weakly supervised dataset based on a teacher/student paradigm that leverages a large collection of unlabelled dialogues. Furthermore, we built a modular dialogue system and integrated coarse-to-fine grained classification for user intent detection. Experiments show that our method can reach the dialog goal with a higher success rate and generate more coherent responses.

本文对过去二十年来对自然语言生成（NLG）的研究提供了全面的审查，特别是与数据到文本生成和文本到文本生成深度学习方法有关，以及NLG的新应用技术。该调查旨在（a）给出关于NLG核心任务的最新综合，以及该领域采用的建筑;（b）详细介绍各种NLG任务和数据集，并提请注意NLG评估中的挑战，专注于不同的评估方法及其关系;（c）强调一些未来的强调和相对近期的研究问题，因为NLG和其他人工智能领域的协同作用而增加，例如计算机视觉，文本和计算创造力。

我们介绍了Godel（接地开放对话语言模型），这是对话框的大型预训练的语言模型。与诸如Dialogpt之类的早期模型相比，Godel利用了一个新的扎根预训练阶段，旨在更好地支持将Godel适应广泛的下游对话框任务，这些任务需要当前对话外部的信息（例如，数据库或文档）到产生良好的回应。针对一系列基准测试的实验，这些基准涵盖了面向任务的对话框，对话质量质量检查和接地的开放式对话框，表明Godel在几次以上的微调设置中优于最先进的预训练的对话模型，就人类和自动评估。我们评估方法的一个新颖特征是引入了一个效用概念，该概念除了其交流特征（内在评估）外，还评估了响应的有用性（外部评估）。我们表明，外部评估提供了改进的通道间一致性和与自动指标的相关性。代码和数据处理脚本公开可用。

Natural Language Inference (NLI) or Recognizing Textual Entailment (RTE) aims at predicting the relation between a pair of sentences (premise and hypothesis) as entailment, contradiction or semantic independence. Although deep learning models have shown promising performance for NLI in recent years, they rely on large scale expensive human-annotated datasets. Semi-supervised learning (SSL) is a popular technique for reducing the reliance on human annotation by leveraging unlabeled data for training. However, despite its substantial success on single sentence classification tasks where the challenge in making use of unlabeled data is to assign "good enough" pseudo-labels, for NLI tasks, the nature of unlabeled data is more complex: one of the sentences in the pair (usually the hypothesis) along with the class label are missing from the data and require human annotations, which makes SSL for NLI more challenging. In this paper, we propose a novel way to incorporate unlabeled data in SSL for NLI where we use a conditional language model, BART to generate the hypotheses for the unlabeled sentences (used as premises). Our experiments show that our SSL framework successfully exploits unlabeled data and substantially improves the performance of four NLI datasets in low-resource settings. We release our code at: https://github.com/msadat3/SSL_for_NLI.

我们介绍了AARGH，这是一个面向任务的对话框系统，该系统结合了单个模型中的检索和生成方法，旨在改善对话框管理和输出的词汇多样性。该模型采用了一种新的响应选择方法，该方法基于动作感知训练目标和简化的单编码检索架构，该方法使我们能够构建端到端检索增强生成模型，在该模型中，检索和生成共享大多数参数。在Multiwoz数据集上，我们表明我们的方法与最先进的基线相比，在维持或改善状态跟踪和上下文响应生成性能的同时，产生了更多的输出。

预先接受的语言模型（PLM）在神经对话建模中标志着巨大的飞跃。虽然PLMS在大型文本语料库上进行预先培训，但通常在具有特定领域知识和对话风格的稀缺对话数据上进行微调。然而，在大型预先训练模型中充分利用现有知识的同时定制语言模型仍然是一个挑战。在本文中，我们提出了一种预先接受训练的对话建模的新方法，将对话生成问题作为一个快速学习任务。而不是在有限的对话数据上进行微调，我们的方法，DialogPrompt学习针对对话背景优化的连续提示嵌入，从而从大型预训练模型中促进了知识。为了鼓励模型更好地利用提示嵌入，提示编码器被设计为在输入对话框上下文中的条件。流行对话数据集的实验表明，我们的方法显着优于微调基线和通用及时学习方法。此外，人类评估强烈支持对DialialPrompt的优越性在响应生成质量方面。