会话问题生成（CQG）是机器通过对话等人类（例如交互式阅读理解）的重要任务。与传统的单转交问题（SQG）相比，CQG更具挑战性的意义，即生成的问题不仅需要有意义，而且要与发生的对话历史保持一致。虽然先前的研究主要集中于如何建模对话的流量和对齐，但迄今为止，尚无对模型必需部分和历史的部分进行全面的研究。我们认为，缩短上下文和历史是至关重要的，因为它可以帮助该模型对对话的一致性进行更多优化。为此，我们提出了一个两阶段CQG框架COHS-CQG，该框架采用COHS模块来缩短输入的上下文和历史记录。特别是，COHS选择连续的句子，并根据其相关性得分通过顶级P策略转弯。我们的模型在答案感和答案环境中都可以在COQA上实现最先进的表演。

哪种卷积神经网络（CNN）结构表现良好的问题令人着迷。在这项工作中，我们通过连接零稳定性和模型性能，再通过一步向答案转向答案。具体而言，我们发现，如果普通微分方程的离散求解器为零稳定，则与该求解器相对应的CNN表现良好。我们首先在深度学习的背景下对零稳定性进行解释，然后在不同的零稳定情况下研究现有的一阶和二阶CNN的性能。基于初步观察，我们为构建CNN提供了高阶离散化，然后提出了一个零稳定的网络（ZeroSNET）。为了确保零稳定性的零稳定性，我们首先推断出满足一致性条件的结构，然后给出无训练参数的零稳定区域。通过分析特征方程的根，我们从理论上获得特征图的最佳系数。从经验上讲，我们从三个方面介绍了结果：我们提供了不同数据集上不同深度的广泛经验证据，以表明特征方程式的根源是需要历史特征的CNN表现的关键；我们的实验表明，零值优于基于高级离散化的现有CNN。零件在输入上显示出更好的鲁棒性。源代码可在\ url {https://github.com/longjin-lab/zerosnet}中获得。

在宣传，新闻和社交媒体中的虚假，不准确和误导信息中，现实世界的问题应答（QA）系统面临综合和推理相互矛盾的挑战，以获得正确答案的挑战。这种紧迫性导致需要使QA系统对错误信息的强大，这是一个先前未开发的主题。我们通过调查与实际和虚假信息混合的矛盾的情况下，通过调查QA模型的行为来研究对QA模型的错误信息的风险。我们为此问题创建了第一个大规模数据集，即对QA，其中包含超过10K的人写和模型生成的矛盾的上下文。实验表明，QA模型易受误导的背景下的攻击。为了防御这种威胁，我们建立一个错误信息感知的QA系统作为一个反措施，可以以联合方式整合问题应答和错误信息检测。

在知识库（复杂KBQA）上回答的复杂问题是具有挑战性的，因为它需要各种组成推理功能，例如多跳推断，属性比较，集合操作。现有的基准有一些缺点，这些缺点限制了复杂的KBQA的发展：1）它们仅提供质量检查对而没有明确的推理过程； 2）问题的多样性或规模很差。为此，我们介绍了KQA Pro，这是一个用于复杂KBQA的数据集，包括〜120k多样化的自然语言问题。我们引入了一种构图和可解释的编程语言KOPL，以表示复杂问题的推理过程。对于每个问题，我们都提供相应的KOPL程序和SPARQL查询，因此KQA Pro可用于KBQA和语义解析任务。实验结果表明，SOTA KBQA方法无法像当前数据集上的KQA Pro上实现有希望的结果，这表明KQA Pro具有挑战性，复杂的KBQA需要进一步的研究工作。我们还将KQA Pro视为用于测试多种推理技能的诊断数据集，对现有模型进行彻底评估，并讨论复杂KBQA的进一步说明。我们的代码和数据集可以从https://github.com/shijx12/kqapro_baselines获得。

Deep learning models can achieve high accuracy when trained on large amounts of labeled data. However, real-world scenarios often involve several challenges: Training data may become available in installments, may originate from multiple different domains, and may not contain labels for training. Certain settings, for instance medical applications, often involve further restrictions that prohibit retention of previously seen data due to privacy regulations. In this work, to address such challenges, we study unsupervised segmentation in continual learning scenarios that involve domain shift. To that end, we introduce GarDA (Generative Appearance Replay for continual Domain Adaptation), a generative-replay based approach that can adapt a segmentation model sequentially to new domains with unlabeled data. In contrast to single-step unsupervised domain adaptation (UDA), continual adaptation to a sequence of domains enables leveraging and consolidation of information from multiple domains. Unlike previous approaches in incremental UDA, our method does not require access to previously seen data, making it applicable in many practical scenarios. We evaluate GarDA on two datasets with different organs and modalities, where it substantially outperforms existing techniques.

The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.

As one of the prevalent methods to achieve automation systems, Imitation Learning (IL) presents a promising performance in a wide range of domains. However, despite the considerable improvement in policy performance, the corresponding research on the explainability of IL models is still limited. Inspired by the recent approaches in explainable artificial intelligence methods, we proposed a model-agnostic explaining framework for IL models called R2RISE. R2RISE aims to explain the overall policy performance with respect to the frames in demonstrations. It iteratively retrains the black-box IL model from the randomized masked demonstrations and uses the conventional evaluation outcome environment returns as the coefficient to build an importance map. We also conducted experiments to investigate three major questions concerning frames' importance equality, the effectiveness of the importance map, and connections between importance maps from different IL models. The result shows that R2RISE successfully distinguishes important frames from the demonstrations.

Compressed videos often exhibit visually annoying artifacts, known as Perceivable Encoding Artifacts (PEAs), which dramatically degrade video visual quality. Subjective and objective measures capable of identifying and quantifying various types of PEAs are critical in improving visual quality. In this paper, we investigate the influence of four spatial PEAs (i.e. blurring, blocking, bleeding, and ringing) and two temporal PEAs (i.e. flickering and floating) on video quality. For spatial artifacts, we propose a visual saliency model with a low computational cost and higher consistency with human visual perception. In terms of temporal artifacts, self-attention based TimeSFormer is improved to detect temporal artifacts. Based on the six types of PEAs, a quality metric called Saliency-Aware Spatio-Temporal Artifacts Measurement (SSTAM) is proposed. Experimental results demonstrate that the proposed method outperforms state-of-the-art metrics. We believe that SSTAM will be beneficial for optimizing video coding techniques.

We propose a distributionally robust return-risk model for Markov decision processes (MDPs) under risk and reward ambiguity. The proposed model optimizes the weighted average of mean and percentile performances, and it covers the distributionally robust MDPs and the distributionally robust chance-constrained MDPs (both under reward ambiguity) as special cases. By considering that the unknown reward distribution lies in a Wasserstein ambiguity set, we derive the tractable reformulation for our model. In particular, we show that that the return-risk model can also account for risk from uncertain transition kernel when one only seeks deterministic policies, and that a distributionally robust MDP under the percentile criterion can be reformulated as its nominal counterpart at an adjusted risk level. A scalable first-order algorithm is designed to solve large-scale problems, and we demonstrate the advantages of our proposed model and algorithm through numerical experiments.

Witnessing the impressive achievements of pre-training techniques on large-scale data in the field of computer vision and natural language processing, we wonder whether this idea could be adapted in a grab-and-go spirit, and mitigate the sample inefficiency problem for visuomotor driving. Given the highly dynamic and variant nature of the input, the visuomotor driving task inherently lacks view and translation invariance, and the visual input contains massive irrelevant information for decision making, resulting in predominant pre-training approaches from general vision less suitable for the autonomous driving task. To this end, we propose PPGeo (Policy Pre-training via Geometric modeling), an intuitive and straightforward fully self-supervised framework curated for the policy pretraining in visuomotor driving. We aim at learning policy representations as a powerful abstraction by modeling 3D geometric scenes on large-scale unlabeled and uncalibrated YouTube driving videos. The proposed PPGeo is performed in two stages to support effective self-supervised training. In the first stage, the geometric modeling framework generates pose and depth predictions simultaneously, with two consecutive frames as input. In the second stage, the visual encoder learns driving policy representation by predicting the future ego-motion and optimizing with the photometric error based on current visual observation only. As such, the pre-trained visual encoder is equipped with rich driving policy related representations and thereby competent for multiple visuomotor driving tasks. Extensive experiments covering a wide span of challenging scenarios have demonstrated the superiority of our proposed approach, where improvements range from 2% to even over 100% with very limited data. Code and models will be available at https://github.com/OpenDriveLab/PPGeo.