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.

将机器学习算法转换为临床应用需要解决与解释性有关的挑战，例如考虑混杂变量（或元数据）的影响。混杂变量会影响输入训练数据和目标输出之间的关系。当我们在此类数据上训练模型时，混杂的变量会偏向于学习功能的分布。最近有前途的解决方案元数据归一化（MDN）估计了基于不可训练的封闭形式解决方案的元数据与每个特征之间的线性关系。但是，该估计受到迷你批量的样本量的限制，因此可能导致该方法在训练过程中不稳定。在本文中，我们通过应用罚款方法（称为PDMN）扩展了MDN方法。我们将问题投入到双层嵌套的优化问题中。然后，我们使用惩罚方法近似此优化问题，以便MDN层中的线性参数可以训练并在所有样本上学习。这使PMDN可以插入任何架构，甚至可以运行批处理级操作，例如变形金刚和经常性模型。我们在合成实验中使用PMDN和MDN的混杂因素和更大的独立性表现出了更大的独立性，并且在合成实验中和多标签的多站点的磁共振图像数据集（MRIS）。

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。

深层生成模型已成为检测数据中任意异常的有前途的工具，并分配了手动标记的必要性。最近，自回旋变压器在医学成像中取得了最先进的性能。但是，这些模型仍然具有一些内在的弱点，例如需要将图像建模为1D序列，在采样过程中误差的积累以及与变压器相关的显着推理时间。去核扩散概率模型是一类非自动回旋生成模型，最近显示出可以在计算机视觉中产生出色的样品（超过生成的对抗网络），并实现与变压器具有竞争力同时具有快速推理时间的对数可能性。扩散模型可以应用于自动编码器学到的潜在表示，使其易于扩展，并适用于高维数据（例如医学图像）的出色候选者。在这里，我们提出了一种基于扩散模型的方法，以检测和分段脑成像中的异常。通过在健康数据上训练模型，然后探索其在马尔可夫链上的扩散和反向步骤，我们可以识别潜在空间中的异常区域，因此可以确定像素空间中的异常情况。我们的扩散模型与一系列具有2D CT和MRI数据的实验相比，具有竞争性能，涉及合成和实际病理病变，推理时间大大减少，从而使它们的用法在临床上可行。

联合学习允许一组分布式客户端培训私有数据的公共机器学习模型。模型更新的交换由中央实体或以分散的方式管理，例如，由一个区间的。但是，所有客户端的强大概括都使得这些方法不合适，不合适地分布（非IID）数据。我们提出了一个统一的统一方法，在联合学习中的权力下放和个性化，该方法是基于模型更新的定向非循环图（DAG）。客户端代替培训单个全局模型，客户端专门从事来自其他客户端的模型更新的本地数据，而不是依赖于各自数据的相似性。这种专业化从基于DAG的沟通和模型更新的选择隐含地出现。因此，我们启用专业模型的演变，它专注于数据的子集，因此覆盖非IID数据，而不是在基于区块的基于区块的设置中的联合学习。据我们所知，拟议的解决方案是第一个在完全分散的联邦学习中团结的个性化和中毒鲁棒性。我们的评价表明，模型的专业化直接从基于DAG的模型更新通信到三个不同的数据集。此外，与联合平均相比，我们在客户端展示稳定的模型精度和更少的方差。

尽管近期因因果推断领域的进展，迄今为止没有关于从观察数据的收集治疗效应估算的方法。对临床实践的结果是，当缺乏随机试验的结果时，没有指导在真实情景中似乎有效的指导。本文提出了一种务实的方法，以获得从观察性研究的治疗效果的初步但稳健地估算，为前线临床医生提供对其治疗策略的信心程度。我们的研究设计适用于一个公开问题，估算Covid-19密集护理患者的拳击机动的治疗效果。

We present a dynamic path planning algorithm to navigate an amphibious rotor craft through a concave time-invariant obstacle field while attempting to minimize energy usage. We create a nonlinear quaternion state model that represents the rotor craft dynamics above and below the water. The 6 degree of freedom dynamics used within a layered architecture to generate motion paths for the vehicle to follow and the required control inputs. The rotor craft has a 3 dimensional map of its surroundings that is updated via limited range onboard sensor readings within the current medium (air or water). Path planning is done via PRM and D* Lite.

The success of neural networks builds to a large extent on their ability to create internal knowledge representations from real-world high-dimensional data, such as images, sound, or text. Approaches to extract and present these representations, in order to explain the neural network's decisions, is an active and multifaceted research field. To gain a deeper understanding of a central aspect of this field, we have performed a targeted review focusing on research that aims to associate internal representations with human understandable concepts. In doing this, we added a perspective on the existing research by using primarily deductive nomological explanations as a proposed taxonomy. We find this taxonomy and theories of causality, useful for understanding what can be expected, and not expected, from neural network explanations. The analysis additionally uncovers an ambiguity in the reviewed literature related to the goal of model explainability; is it understanding the ML model or, is it actionable explanations useful in the deployment domain?

Many problems in machine learning involve bilevel optimization (BLO), including hyperparameter optimization, meta-learning, and dataset distillation. Bilevel problems consist of two nested sub-problems, called the outer and inner problems, respectively. In practice, often at least one of these sub-problems is overparameterized. In this case, there are many ways to choose among optima that achieve equivalent objective values. Inspired by recent studies of the implicit bias induced by optimization algorithms in single-level optimization, we investigate the implicit bias of gradient-based algorithms for bilevel optimization. We delineate two standard BLO methods -- cold-start and warm-start -- and show that the converged solution or long-run behavior depends to a large degree on these and other algorithmic choices, such as the hypergradient approximation. We also show that the inner solutions obtained by warm-start BLO can encode a surprising amount of information about the outer objective, even when the outer parameters are low-dimensional. We believe that implicit bias deserves as central a role in the study of bilevel optimization as it has attained in the study of single-level neural net optimization.

An expansion of aberrant brain cells is referred to as a brain tumor. The brain's architecture is extremely intricate, with several regions controlling various nervous system processes. Any portion of the brain or skull can develop a brain tumor, including the brain's protective coating, the base of the skull, the brainstem, the sinuses, the nasal cavity, and many other places. Over the past ten years, numerous developments in the field of computer-aided brain tumor diagnosis have been made. Recently, instance segmentation has attracted a lot of interest in numerous computer vision applications. It seeks to assign various IDs to various scene objects, even if they are members of the same class. Typically, a two-stage pipeline is used to perform instance segmentation. This study shows brain cancer segmentation using YOLOv5. Yolo takes dataset as picture format and corresponding text file. You Only Look Once (YOLO) is a viral and widely used algorithm. YOLO is famous for its object recognition properties. You Only Look Once (YOLO) is a popular algorithm that has gone viral. YOLO is well known for its ability to identify objects. YOLO V2, V3, V4, and V5 are some of the YOLO latest versions that experts have published in recent years. Early brain tumor detection is one of the most important jobs that neurologists and radiologists have. However, it can be difficult and error-prone to manually identify and segment brain tumors from Magnetic Resonance Imaging (MRI) data. For making an early diagnosis of the condition, an automated brain tumor detection system is necessary. The model of the research paper has three classes. They are respectively Meningioma, Pituitary, Glioma. The results show that, our model achieves competitive accuracy, in terms of runtime usage of M2 10 core GPU.