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.

Large language models (LLMs) have been shown to be able to perform new tasks based on a few demonstrations or natural language instructions. While these capabilities have led to widespread adoption, most LLMs are developed by resource-rich organizations and are frequently kept from the public. As a step towards democratizing this powerful technology, we present BLOOM, a 176B-parameter open-access language model designed and built thanks to a collaboration of hundreds of researchers. BLOOM is a decoder-only Transformer language model that was trained on the ROOTS corpus, a dataset comprising hundreds of sources in 46 natural and 13 programming languages (59 in total). We find that BLOOM achieves competitive performance on a wide variety of benchmarks, with stronger results after undergoing multitask prompted finetuning. To facilitate future research and applications using LLMs, we publicly release our models and code under the Responsible AI License.

对于场景重建和新型视图综合的数量表示形式的普及最近，人们的普及使重点放在以高视觉质量和实时为实时的体积内容动画上。尽管基于学习功能的隐性变形方法可以产生令人印象深刻的结果，但它们是艺术家和内容创建者的“黑匣子”，但它们需要大量的培训数据才能有意义地概括，并且在培训数据之外不会产生现实的外推。在这项工作中，我们通过引入实时的音量变形方法来解决这些问题，该方法是实时的，易于使用现成的软件编辑，并且可以令人信服地推断出来。为了证明我们方法的多功能性，我们将其应用于两种情况：基于物理的对象变形和触发性，其中使用Blendshapes控制着头像。我们还进行了彻底的实验，表明我们的方法与两种体积方法相比，结合了基于网格变形的隐式变形和方法。

地标通常在面部分析中起关键作用，但是仅凭稀疏地标就不能代表身份或表达的许多方面。因此，为了更准确地重建面，地标通常与其他信号（如深度图像或技术）相结合，例如可区分渲染。我们可以通过使用更多地标使事情变得简单吗？在答案中，我们提出了第一种准确地预测10倍地标的方法，覆盖整个头部，包括眼睛和牙齿。这是使用合成培训数据来完成的，该数据保证了完美的地标注释。通过将可变形的模型拟合到这些密集的地标，我们可以在野外实现单眼3D面重建的最新结果。我们表明，密集的地标是通过在单眼和多视图方案中展示准确和表现力的面部绩效捕获来整合跨帧面部形状信息的理想信号。这种方法也非常有效：我们可以预测密集的地标，并在单个CPU线程上以超过150fps的速度适合我们的3D面模型。请参阅我们的网站：https：//microsoft.github.io/denselandmarks/。

以准确的，稳健和快速的方式拟合人体，手或面对稀疏输入信号的参数模型，这具有重要的是在AR和VR场景中显着改善浸入。解决这些问题的系统中的一个常见的第一步是直接从输入数据重新分配参数模型的参数。这种方法是快速，稳健的，并且是迭代最小化算法的良好起点。后者搜索最小的能量函数，通常由编码关于问题的结构的知识的数据项和前沿组成。虽然这无疑是一个非常成功的食谱，但前锋往往是手工定义的启发式，发现不同术语之间的正确平衡，以实现高质量的结果是一个非琐碎的任务。此外，转换和优化这些系统以表现方式运行，需要定制实现，要求从工程师和域专家进行大量时间投资。在这项工作中，我们建立了近期学习优化的进步，并提出了由Classic Levenberg-Marquardt算法启发的更新规则。我们展示了所提出的神经优化器对从2D地标的头戴式装置和面部配件的3D体表估计问题的有效性。我们的方法可以很容易地应用于新的模型拟合问题，并提供竞争替代方案，在准确性和速度方面都提供了良好的调谐“传统”模型拟合管道。

The goal of this paper is to estimate the 6D pose and dimensions of unseen object instances in an RGB-D image. Contrary to "instance-level" 6D pose estimation tasks, our problem assumes that no exact object CAD models are available during either training or testing time. To handle different and unseen object instances in a given category, we introduce Normalized Object Coordinate Space (NOCS)-a shared canonical representation for all possible object instances within a category. Our region-based neural network is then trained to directly infer the correspondence from observed pixels to this shared object representation (NOCS) along with other object information such as class label and instance mask. These predictions can be combined with the depth map to jointly estimate the metric 6D pose and dimensions of multiple objects in a cluttered scene. To train our network, we present a new contextaware technique to generate large amounts of fully annotated mixed reality data. To further improve our model and evaluate its performance on real data, we also provide a fully annotated real-world dataset with large environment and instance variation. Extensive experiments demonstrate that the proposed method is able to robustly estimate the pose and size of unseen object instances in real environments while also achieving state-of-the-art performance on standard 6D pose estimation benchmarks.

In this paper, we address the problem of multimodal emotion recognition from multiple physiological signals. We demonstrate that a Transformer-based approach is suitable for this task. In addition, we present how such models may be pretrained in a multimodal scenario to improve emotion recognition performances. We evaluate the benefits of using multimodal inputs and pre-training with our approach on a state-ofthe-art dataset.

Contrastive representation learning has proven to be an effective self-supervised learning method for images and videos. Most successful approaches are based on Noise Contrastive Estimation (NCE) and use different views of an instance as positives that should be contrasted with other instances, called negatives, that are considered as noise. However, several instances in a dataset are drawn from the same distribution and share underlying semantic information. A good data representation should contain relations between the instances, or semantic similarity and dissimilarity, that contrastive learning harms by considering all negatives as noise. To circumvent this issue, we propose a novel formulation of contrastive learning using semantic similarity between instances called Similarity Contrastive Estimation (SCE). Our training objective is a soft contrastive one that brings the positives closer and estimates a continuous distribution to push or pull negative instances based on their learned similarities. We validate empirically our approach on both image and video representation learning. We show that SCE performs competitively with the state of the art on the ImageNet linear evaluation protocol for fewer pretraining epochs and that it generalizes to several downstream image tasks. We also show that SCE reaches state-of-the-art results for pretraining video representation and that the learned representation can generalize to video downstream tasks.

We propose a fully unsupervised method to detect bias in contextualized embeddings. The method leverages the assortative information latently encoded by social networks and combines orthogonality regularization, structured sparsity learning, and graph neural networks to find the embedding subspace capturing this information. As a concrete example, we focus on the phenomenon of ideological bias: we introduce the concept of an ideological subspace, show how it can be found by applying our method to online discussion forums, and present techniques to probe it. Our experiments suggest that the ideological subspace encodes abstract evaluative semantics and reflects changes in the political left-right spectrum during the presidency of Donald Trump.

Information spread on networks can be efficiently modeled by considering three features: documents' content, time of publication relative to other publications, and position of the spreader in the network. Most previous works model up to two of those jointly, or rely on heavily parametric approaches. Building on recent Dirichlet-Point processes literature, we introduce the Houston (Hidden Online User-Topic Network) model, that jointly considers all those features in a non-parametric unsupervised framework. It infers dynamic topic-dependent underlying diffusion networks in a continuous-time setting along with said topics. It is unsupervised; it considers an unlabeled stream of triplets shaped as \textit{(time of publication, information's content, spreading entity)} as input data. Online inference is conducted using a sequential Monte-Carlo algorithm that scales linearly with the size of the dataset. Our approach yields consequent improvements over existing baselines on both cluster recovery and subnetworks inference tasks.