大自然的一个迷人方面在于它能够产生大型和多样化的生物体，这些生物都在他们的利基中都很高兴。相比之下，大多数AI算法专注于向给定问题找到一个有效的解决方案。除了表现外，旨在实现多样性是处理勘探开发权衡的便捷方式，在学习中发挥着核心作用。当返回的集合包含对所考虑的问题的几个工作解决方案时，它还允许增加鲁棒性，使其适用于机器人等真实应用。质量 - 多样性（QD）方法是为此目的设计的进化算法。本文提出了一种新颖的QD - PG，它结合了政策梯度算法的强度和质量多样性方法，在连续控制环境中产生了各种和高性能的神经政策的集合。这项工作的主要贡献是引入多样性政策梯度（DPG），该梯度（DPG）利用时刻级别的信息以采样有效的方式培养更多样化的策略。具体而言，QD-PG从地图 - E LITES网格中选择神经控制器，并使用两个基于梯度的突变运算符来提高质量和多样性，从而产生稳定的人口更新。我们的结果表明，QD - PG产生了各种解决方案的集合，解决了具有挑战性的勘探和控制问题，同时是比其进化竞争对手更高的样本效率的两个数量级。

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.

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.

Classifying forecasting methods as being either of a "machine learning" or "statistical" nature has become commonplace in parts of the forecasting literature and community, as exemplified by the M4 competition and the conclusion drawn by the organizers. We argue that this distinction does not stem from fundamental differences in the methods assigned to either class. Instead, this distinction is probably of a tribal nature, which limits the insights into the appropriateness and effectiveness of different forecasting methods. We provide alternative characteristics of forecasting methods which, in our view, allow to draw meaningful conclusions. Further, we discuss areas of forecasting which could benefit most from cross-pollination between the ML and the statistics communities.

Incorporating prior knowledge of physics laws and structural properties of dynamical systems into the design of deep learning architectures has proven to be a powerful technique for improving their computational efficiency and generalization capacity. Learning accurate models of robot dynamics is critical for safe and stable control. Autonomous mobile robots, including wheeled, aerial, and underwater vehicles, can be modeled as controlled Lagrangian or Hamiltonian rigid-body systems evolving on matrix Lie groups. In this paper, we introduce a new structure-preserving deep learning architecture, the Lie group Forced Variational Integrator Network (LieFVIN), capable of learning controlled Lagrangian or Hamiltonian dynamics on Lie groups, either from position-velocity or position-only data. By design, LieFVINs preserve both the Lie group structure on which the dynamics evolve and the symplectic structure underlying the Hamiltonian or Lagrangian systems of interest. The proposed architecture learns surrogate discrete-time flow maps instead of surrogate vector fields, which allows better and faster prediction without requiring the use of a numerical integrator, neural ODE, or adjoint techniques. Furthermore, the learnt discrete-time dynamics can be combined seamlessly with computationally scalable discrete-time (optimal) control strategies.

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.

Denoising diffusions are state-of-the-art generative models which exhibit remarkable empirical performance and come with theoretical guarantees. The core idea of these models is to progressively transform the empirical data distribution into a simple Gaussian distribution by adding noise using a diffusion. We obtain new samples whose distribution is close to the data distribution by simulating a "denoising" diffusion approximating the time reversal of this "noising" diffusion. This denoising diffusion relies on approximations of the logarithmic derivatives of the noised data densities, known as scores, obtained using score matching. Such models can be easily extended to perform approximate posterior simulation in high-dimensional scenarios where one can only sample from the prior and simulate synthetic observations from the likelihood. These methods have been primarily developed for data on $\mathbb{R}^d$ while extensions to more general spaces have been developed on a case-by-case basis. We propose here a general framework which not only unifies and generalizes this approach to a wide class of spaces but also leads to an original extension of score matching. We illustrate the resulting class of denoising Markov models on various applications.

The heterogeneity of hardware and data is a well-known and studied problem in the community of Federated Learning (FL) as running under heterogeneous settings. Recently, custom-size client models trained with Knowledge Distillation (KD) has emerged as a viable strategy for tackling the heterogeneity challenge. However, previous efforts in this direction are aimed at client model tuning rather than their impact onto the knowledge aggregation of the global model. Despite performance of global models being the primary objective of FL systems, under heterogeneous settings client models have received more attention. Here, we provide more insights into how the chosen approach for training custom client models has an impact on the global model, which is essential for any FL application. We show the global model can fully leverage the strength of KD with heterogeneous data. Driven by empirical observations, we further propose a new approach that combines KD and Learning without Forgetting (LwoF) to produce improved personalised models. We bring heterogeneous FL on pair with the mighty FedAvg of homogeneous FL, in realistic deployment scenarios with dropping clients.

事实证明，基于得分的生成建模（SGM）是对有限维空间建模密度的非常有效的方法。在这项工作中，我们建议将这种方法扩展到在功能空间上学习生成模型。为此，我们代表光谱空间中的功能数据，以将过程的随机部分与其时空部分解离。然后，我们使用有限尺寸SGM从其随机组件中采样了尺寸降低技术。我们证明了我们的方法对各种多模式数据集进行建模的有效性。

机器人系统的控制设计很复杂，通常需要解决优化才能准确遵循轨迹。在线优化方法（例如模型预测性控制（MPC））已被证明可以实现出色的跟踪性能，但需要高计算能力。相反，基于学习的离线优化方法，例如加固学习（RL），可以在机器人上快速有效地执行，但几乎不匹配MPC在轨迹跟踪任务中的准确性。在具有有限计算的系统（例如航空车）中，必须在执行时间有效的精确控制器。我们提出了一种分析策略梯度（APG）方法来解决此问题。 APG通过在跟踪误差上以梯度下降的速度训练控制器来利用可区分的模拟器的可用性。我们解决了通过课程学习和实验经常在广泛使用的控制基准，Cartpole和两个常见的空中机器人，一个四极管和固定翼无人机上进行的训练不稳定性。在跟踪误差方面，我们提出的方法优于基于模型和无模型的RL方法。同时，它达到与MPC相似的性能，同时需要少于数量级的计算时间。我们的工作为APG作为机器人技术的有前途的控制方法提供了见解。为了促进对APG的探索，我们开放代码并在https://github.com/lis-epfl/apg_traightory_tracking上提供。