现有的假新闻检测方法旨在将新闻分类为真或错误，并提供真实的解释，从而实现出色的表现。但是，他们经常根据有限的新闻报道和揭穿延误来定制手动事实检查报告的自动解决方案。如果尚未对一段新闻进行事实检查或揭穿事实，通常会在各种媒体上传播一定数量的相关原始报告，其中包含人群的智慧来验证新闻声明并解释其判决。在本文中，我们提出了一个新颖的粗到十五级别的级联证据依据（COFCED）神经网络，以根据此类原始报告来解释假新闻检测，从而减轻了对事实检查的依赖性。具体而言，我们首先使用层次结构编码器来用于Web文本表示，然后开发两个级联的选择器，以粗略至上的方式在所选的Top-K报告之上选择最可解释的句子。此外，我们构建了两个可解释的假新闻数据集，这些数据集可公开使用。实验结果表明，我们的模型显着优于最先进的基线，并从不同的评估角度产生高质量的解释。

强化学习的主要困难之一是从{\ em dobsolicy}样本中学习，这些样本是由算法评估（目标策略）的不同策略（行为策略）收集的。非政策学习需要从行为政策中纠正样本的分布到目标策略的分布。不幸的是，重要的抽样具有固有的高方差问题，从而导致策略梯度方法的梯度估计差。我们专注于范围的参与者 - 批评体系结构，并提出了一种称为预处理近端政策优化（P3O）的新方法，该方法可以通过将预处理程序应用于保守政策迭代（CPI）目标来控制重要性采样的较高差异。 {\ em此预处理以一种特殊的方式使用Sigmoid函数，即当没有策略更改时，梯度是最大的，因此策略梯度将驱动大参数更新以有效地探索参数空间}。这是一种新颖的探索方法，鉴于现有的探索方法是基于国家和行动的新颖性，尚未对其进行研究。我们与离散和连续任务上的几种表现最好的算法进行了比较，结果表明{\ em ppo不足以实现异位}，并且我们的p3O比ppo {\ em off-policy}比ppo比“根据off off ppo”。 - 通过Deon Metric衡量的Policyness，P3O在比PPO更大的政策空间中探索。结果还表明，在训练过程中，我们的P3O比PPO更好地提高了CPI目标。

单击后键盘转换为指示用户偏好的强信号，是构建推荐系统的良性。但是，由于选择偏差，即，观察到的单击事件通常会发生在用户的首选项目，准确地估计点击后击率（CVR）是具有挑战性的。目前，大多数现有方法利用反事实学习到Debias推荐系统。其中，双重稳健（DR）估计器通过以双重稳健的方式组合基于误差估算的（EIB）估计和逆倾向分数（IPS）估计来实现竞争性能。然而，不准确的误差估算可能导致其比IPS估计器更高的方差。更糟糕的是，现有方法通常使用简单的模型 - 不可知方法来估计归纳错误，这不足以近似于近似于动态改变的模型相关目标（即预测模型的梯度方向）。为了解决这些问题，我们首先导出DR估算器的偏差和方差。基于它，已经提出了一种更强大的双重稳健（MRDR）估计器，以进一步降低其差异，同时保持其双重稳健性。此外，我们为MRDR估算器提出了一种新的双重学习方法，可以将误差归纳转换为一般的CVR估计。此外，我们经验验证所提出的学习方案可以进一步消除估算学习的高方差问题。为了评估其有效性，在半合成数据集和两个现实世界数据集上进行了广泛的实验。结果证明了所提出的方法的优越性在最先进的方法中。代码可在https://github.com/guosyjlu/mrdr-dl上获得。

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.

As one of the most important psychic stress reactions, micro-expressions (MEs), are spontaneous and transient facial expressions that can reveal the genuine emotions of human beings. Thus, recognizing MEs (MER) automatically is becoming increasingly crucial in the field of affective computing, and provides essential technical support in lie detection, psychological analysis and other areas. However, the lack of abundant ME data seriously restricts the development of cutting-edge data-driven MER models. Despite the recent efforts of several spontaneous ME datasets to alleviate this problem, it is still a tiny amount of work. To solve the problem of ME data hunger, we construct a dynamic spontaneous ME dataset with the largest current ME data scale, called DFME (Dynamic Facial Micro-expressions), which includes 7,526 well-labeled ME videos induced by 671 participants and annotated by more than 20 annotators throughout three years. Afterwards, we adopt four classical spatiotemporal feature learning models on DFME to perform MER experiments to objectively verify the validity of DFME dataset. In addition, we explore different solutions to the class imbalance and key-frame sequence sampling problems in dynamic MER respectively on DFME, so as to provide a valuable reference for future research. The comprehensive experimental results show that our DFME dataset can facilitate the research of automatic MER, and provide a new benchmark for MER. DFME will be published via https://mea-lab-421.github.io.