Late-life depression (LLD) is a highly prevalent mood disorder occurring in older adults and is frequently accompanied by cognitive impairment (CI). Studies have shown that LLD may increase the risk of Alzheimer's disease (AD). However, the heterogeneity of presentation of geriatric depression suggests that multiple biological mechanisms may underlie it. Current biological research on LLD progression incorporates machine learning that combines neuroimaging data with clinical observations. There are few studies on incident cognitive diagnostic outcomes in LLD based on structural MRI (sMRI). In this paper, we describe the development of a hybrid representation learning (HRL) framework for predicting cognitive diagnosis over 5 years based on T1-weighted sMRI data. Specifically, we first extract prediction-oriented MRI features via a deep neural network, and then integrate them with handcrafted MRI features via a Transformer encoder for cognitive diagnosis prediction. Two tasks are investigated in this work, including (1) identifying cognitively normal subjects with LLD and never-depressed older healthy subjects, and (2) identifying LLD subjects who developed CI (or even AD) and those who stayed cognitively normal over five years. To the best of our knowledge, this is among the first attempts to study the complex heterogeneous progression of LLD based on task-oriented and handcrafted MRI features. We validate the proposed HRL on 294 subjects with T1-weighted MRIs from two clinically harmonized studies. Experimental results suggest that the HRL outperforms several classical machine learning and state-of-the-art deep learning methods in LLD identification and prediction tasks.

The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.

Recently, the success of pre-training in text domain has been fully extended to vision, audio, and cross-modal scenarios. The proposed pre-training models of different modalities are showing a rising trend of homogeneity in their model structures, which brings the opportunity to implement different pre-training models within a uniform framework. In this paper, we present TencentPretrain, a toolkit supporting pre-training models of different modalities. The core feature of TencentPretrain is the modular design. The toolkit uniformly divides pre-training models into 5 components: embedding, encoder, target embedding, decoder, and target. As almost all of common modules are provided in each component, users can choose the desired modules from different components to build a complete pre-training model. The modular design enables users to efficiently reproduce existing pre-training models or build brand-new one. We test the toolkit on text, vision, and audio benchmarks and show that it can match the performance of the original implementations.

Recent works on Lottery Ticket Hypothesis have shown that pre-trained language models (PLMs) contain smaller matching subnetworks(winning tickets) which are capable of reaching accuracy comparable to the original models. However, these tickets are proved to be notrobust to adversarial examples, and even worse than their PLM counterparts. To address this problem, we propose a novel method based on learning binary weight masks to identify robust tickets hidden in the original PLMs. Since the loss is not differentiable for the binary mask, we assign the hard concrete distribution to the masks and encourage their sparsity using a smoothing approximation of L0 regularization.Furthermore, we design an adversarial loss objective to guide the search for robust tickets and ensure that the tickets perform well bothin accuracy and robustness. Experimental results show the significant improvement of the proposed method over previous work on adversarial robustness evaluation.

当前基于RGB的6D对象姿势估计方法在数据集和现实世界应用程序上取得了明显的性能。但是，从单个2D图像特征中预测6D姿势容易受到环境和纹理或相似物体表面的变化的干扰。因此，基于RGB的方法通常比基于RGBD的方法获得的竞争结果较低，后者既部署图像特征和3D结构特征。为了缩小这一性能差距，本文提出了一个6D对象姿势估计的框架，该框架从2个RGB图像中学习隐式3D信息。结合学习的3D信息和2D图像功能，我们在场景和对象模型之间建立了更稳定的对应关系。为了寻求从RGB输入中使用3D信息的最佳方法，我们对三种不同的方法进行了调查，包括早期融合，中融合和晚融合。我们确定中融合方法是恢复最精确的3D关键点的最佳方法，可用于对象姿势估计。该实验表明，我们的方法优于最先进的RGB方法，并通过基于RGBD的方法获得了可比的结果。

语言模型既展示了定量的改进，又展示了新的定性功能，随着规模的增加。尽管它们具有潜在的变革性影响，但这些新能力的特征却很差。为了为未来的研究提供信息，为破坏性的新模型能力做准备，并改善社会有害的效果，至关重要的是，我们必须了解目前和近乎未来的能力和语言模型的局限性。为了应对这一挑战，我们介绍了超越模仿游戏基准（Big Bench）。 Big Bench目前由204个任务组成，由132家机构的442位作者贡献。任务主题是多样的，从语言学，儿童发展，数学，常识性推理，生物学，物理学，社会偏见，软件开发等等。 Big-Bench专注于被认为超出当前语言模型的功能的任务。我们评估了OpenAI的GPT型号，Google内部密集变压器体系结构和大型基础上的开关稀疏变压器的行为，跨越了数百万到数十亿个参数。此外，一个人类专家评估者团队执行了所有任务，以提供强大的基准。研究结果包括：模型性能和校准都随规模改善，但绝对的术语（以及与评估者的性能相比）；在模型类中的性能非常相似，尽管带有稀疏性。逐渐和预测的任务通常涉及大量知识或记忆成分，而在临界规模上表现出“突破性”行为的任务通常涉及多个步骤或组成部分或脆性指标；社交偏见通常会随着含糊不清的环境而随着规模而增加，但这可以通过提示来改善。

联合学习在具有分布式数据的设备上进行模型，同时保护隐私并获取类似于集中式ML的模型。具有数据和计算能力的大量工人是联邦学习的基础。然而，不可避免的成本阻止自私的工人免费服务。此外，由于数据隔离，任务发布者缺乏选择，评估和支付具有高质量数据的可靠工人的有效方法。因此，我们设计了一种基于拍卖的激励机制，具有声誉和贡献测量的横向联合学习。通过设计合理的衡量贡献方法，我们建立了工人的声誉，这很容易下降，难以改善。通过反向拍卖，工人竞标任务，任务发布者选择合作者组合声誉和出价价格。通过预算制约，获奖工人根据业绩支付。我们证明我们的机制满足诚实的工人，预算可行性，真实性和计算效率的个人合理性。

联合学习（FL）是一个带有边缘计算的充填地的新兴分布式机器学习范式，是具有在移动边缘设备上具有新颖应用的有前途的区域。在FL中，由于移动设备通过共享模型更新，因此在中央服务器的协调下基于其自身的数据进行组合培训模型，培训数据保持私密。但是，在没有数据的核心可用性的情况下，计算节点需要经常传送模型更新以获得汇聚。因此，本地计算时间与将本地模型更新一起创建本地模型更新以及从服务器发送到服务器的时间导致总时间的延迟。此外，不可靠的网络连接可以妨碍这些更新的有效通信。为了解决这些问题，我们提出了一个延迟有效的流动机制，可以减少模型融合所需的总时间（包括计算和通信延迟）和通信轮。探索各种参数对延迟的影响，我们寻求平衡无线通信（谈话）和本地计算之间的权衡（为工作）。我们与整体时间作为优化问题制定了关系，并通过广泛的模拟展示了我们方法的功效。

数据增强已广泛用于图像数据和语言数据，但仍然探索图形神经网络（GNN）。现有方法专注于从全局视角增强图表数据，并大大属于两个类型：具有特征噪声注入的结构操纵和对抗训练。但是，最近的图表数据增强方法忽略了GNNS“消息传递机制的本地信息的重要性。在这项工作中，我们介绍了本地增强，这通过其子图结构增强了节点表示的局部。具体而言，我们将数据增强模拟为特征生成过程。鉴于节点的功能，我们的本地增强方法了解其邻居功能的条件分布，并生成更多邻居功能，以提高下游任务的性能。基于本地增强，我们进一步设计了一个新颖的框架：La-GNN，可以以即插即用的方式应用于任何GNN模型。广泛的实验和分析表明，局部增强一致地对各种基准的各种GNN架构始终如一地产生性能改进。

AI正在经历范式转变，随着模型的兴起（例如Bert，Dall-E，GPT-3），这些模型经过大规模的数据训练，并且可以适应广泛的下游任务。我们称这些模型基础模型来强调其至关重要但不完整的特征。该报告提供了基础模型的机会和风险的详尽说明，包括其功能（例如语言，愿景，机器人技术，推理，人类互动）和技术原则（例如，模型架构，培训程序，数据，系统，安全，安全性，评估，理论）对其应用（例如法律，医疗保健，教育）和社会影响（例如不平等，滥用，经济和环境影响，法律和道德考虑）。尽管基础模型基于标准的深度学习和转移学习，但它们的规模导致了新的新兴能力，以及它们在许多任务中的有效性都激发了同质化。同质化提供了强大的杠杆作用，但要求谨慎，因为基础模型的缺陷均由下游的所有适应模型继承。尽管即将广泛地部署基础模型，但我们目前对它们的工作方式，失败以及由于其新兴属性的影响而缺乏清晰的了解。为了解决这些问题，我们认为基础模型的许多批判性研究都需要与他们的基本社会技术性质相称。