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.

在高度波动的加密货币市场中，设计盈利和可靠的交易策略是具有挑战性的。现有作品应用了深厚的增强学习方法，并在回测的乐观上报告了利润增加，这可能会因过度拟合而造成的假积极问题。在本文中，我们提出了一种实用方法，以解决使用深度强化学习的重新测试，以解决加密货币交易。首先，我们将过度拟合的检测作为假设检测。然后，我们训练DRL代理，估计过度拟合的可能性，并拒绝过度拟合的代理商，从而增加了良好交易绩效的机会。最后，在从05/01/2022到06/27/2022（在此期间加密货币市场崩溃两次）的测试期间的10次加密货币中，我们表明，过度拟合的深度强化学习剂的尖锐比率较高。更多过度合适的代理商，同等的权重策略和标准普尔DBM指数（市场基准），对可能部署到真实市场的可能性充满信心。

慢性肾脏疾病（CKD）代表一种缓慢进行的疾病，最终可能需要肾脏替代疗法（RRT），包括透析或肾移植。例如，对需要RRT的患者（提前1年）的早期鉴定可以改善患者的预后，例如，通过允许更高质量的透析血管通道。因此，护理团队对RRT的需求的早期认识是成功管理该疾病的关键。不幸的是，目前没有常用的RRT启动预测工具。在这项工作中，我们提出了一种机器学习模型，该模型可以动态地识别有可能需要RRT的CKD患者，最多只使用索赔数据。为了评估该模型，我们研究了大约300万Medicare受益人，我们做出了超过800万个预测。我们表明该模型可以识别出超过90％敏感性和特异性的风险患者。尽管在准备临床使用之前需要进行其他工作，但本研究为筛查工具提供了一个基础，以在时间窗口内识别有风险的患者，以实现旨在改善RRT结果的早期主动干预措施。

最近显示外部眼睛照片显示出糖尿病性视网膜疾病和HBA1C升高的迹象。在本文中，我们评估外部眼睛照片是否包含有关其他系统性医疗状况的信息。我们开发了一个深度学习系统（DLS），该系统将外部眼睛的照片作为输入，并预测多个全身参数，例如与肝脏有关的参数（白蛋白，AST）；肾脏（EGFR使用无种族的2021 CKD-EPI肌酐方程，尿液ACR）；骨与矿物质（钙）;甲状腺（TSH）;和血数（HGB，WBC，血小板）。开发利用了49,015例糖尿病患者的151,237张图像，在加利福尼亚州洛杉矶县的11个地点接受糖尿病眼镜筛查。评估重点是9个预先指定的全身参数，并利用了3个验证集（a，b，c），涵盖了28,869名患有和没有糖尿病的患者，在加利福尼亚州洛杉矶县和大亚特兰大地区的3个独立地点进行了眼睛筛查。我们将结合了可用临床人口统计学变量的基线模型（例如年龄，性别，种族/种族，糖尿病年）进行了比较。相对于基线，DLS在检测AST> 36，钙<8.6，egfr <60，HGB <11，血小板<150，ACR> = 300和WBC <4时，在检测AST> 36，钙<8.6，Egfr <60，HGB <60，HGB <60，calcium <8.6，Egfr <60，calcium <8.6和wbc <4时，达到了统计学上的显着性能，并且类似于开发集的人口），其中DLS的AUC超过基线的AUC，增长了5.2-19.4％。在验证集B和C方面，与开发集相比，患者人群的差异很大，DLS的表现优于ACR> = 300的基线，而HGB <11升至7.3-13.2％。我们的发现提供了进一步的证据，表明外部眼睛照片包含跨越多器官系统的全身健康生物标志物。需要进一步的工作来研究这些生物标志物是否以及如何转化为临床影响。

机器学习系统对通过风险分数预测患者不良事件的预测显示出了巨大的希望。但是，根据培训数据中存在的干预政策，这些风险分数隐含地编码有关患者可能会接受的未来干预措施的假设。没有这种重要的背景，这些系统的预测对于临床医生而言是不太可解释的。我们提出了一种干预政策和不利事件风险的联合模型，以此作为明确传达模型对未来干预措施的假设的一种手段。我们开发了一种关于Mimic-III的干预政策模型，这是一个现实世界中的ICU数据集，并讨论了一些用例突出该方法的实用性。我们展示了将典型的风险评分（例如死亡率的可能性）与未来干预概率分数相结合，从而导致更明显的临床预测。

强化学习算法的实用性由于相对于问题大小的规模差而受到限制，因为学习$ \ epsilon $ -optimal策略的样本复杂性为$ \ tilde {\ omega} \ left（| s | s || a || a || a || a | h^3 / \ eps^2 \ right）$在MDP的最坏情况下，带有状态空间$ S $，ACTION SPACE $ A $和HORIZON $ H $。我们考虑一类显示出低级结构的MDP，其中潜在特征未知。我们认为，价值迭代和低级别矩阵估计的自然组合导致估计误差在地平线上呈指数增长。然后，我们提供了一种新算法以及统计保证，即有效利用了对生成模型的访问，实现了$ \ tilde {o} \ left的样本复杂度（d^5（d^5（| s |+| a |）\），我们有效利用低级结构。对于等级$ d $设置的Mathrm {Poly}（h）/\ EPS^2 \ right）$，相对于$ | s |，| a | $和$ \ eps $的缩放，这是最小值的最佳。与线性和低级别MDP的文献相反，我们不需要已知的功能映射，我们的算法在计算上很简单，并且我们的结果长期存在。我们的结果提供了有关MDP对过渡内核与最佳动作值函数所需的最小低级结构假设的见解。

Machine learning models are typically evaluated by computing similarity with reference annotations and trained by maximizing similarity with such. Especially in the bio-medical domain, annotations are subjective and suffer from low inter- and intra-rater reliability. Since annotations only reflect the annotation entity's interpretation of the real world, this can lead to sub-optimal predictions even though the model achieves high similarity scores. Here, the theoretical concept of Peak Ground Truth (PGT) is introduced. PGT marks the point beyond which an increase in similarity with the reference annotation stops translating to better Real World Model Performance (RWMP). Additionally, a quantitative technique to approximate PGT by computing inter- and intra-rater reliability is proposed. Finally, three categories of PGT-aware strategies to evaluate and improve model performance are reviewed.

Achieving artificially intelligent-native wireless networks is necessary for the operation of future 6G applications such as the metaverse. Nonetheless, current communication schemes are, at heart, a mere reconstruction process that lacks reasoning. One key solution that enables evolving wireless communication to a human-like conversation is semantic communications. In this paper, a novel machine reasoning framework is proposed to pre-process and disentangle source data so as to make it semantic-ready. In particular, a novel contrastive learning framework is proposed, whereby instance and cluster discrimination are performed on the data. These two tasks enable increasing the cohesiveness between data points mapping to semantically similar content elements and disentangling data points of semantically different content elements. Subsequently, the semantic deep clusters formed are ranked according to their level of confidence. Deep semantic clusters of highest confidence are considered learnable, semantic-rich data, i.e., data that can be used to build a language in a semantic communications system. The least confident ones are considered, random, semantic-poor, and memorizable data that must be transmitted classically. Our simulation results showcase the superiority of our contrastive learning approach in terms of semantic impact and minimalism. In fact, the length of the semantic representation achieved is minimized by 57.22% compared to vanilla semantic communication systems, thus achieving minimalist semantic representations.

Both clustering and outlier detection play an important role for meteorological measurements. We present the AWT algorithm, a clustering algorithm for time series data that also performs implicit outlier detection during the clustering. AWT integrates ideas of several well-known K-Means clustering algorithms. It chooses the number of clusters automatically based on a user-defined threshold parameter, and it can be used for heterogeneous meteorological input data as well as for data sets that exceed the available memory size. We apply AWT to crowd sourced 2-m temperature data with an hourly resolution from the city of Vienna to detect outliers and to investigate if the final clusters show general similarities and similarities with urban land-use characteristics. It is shown that both the outlier detection and the implicit mapping to land-use characteristic is possible with AWT which opens new possible fields of application, specifically in the rapidly evolving field of urban climate and urban weather.

Deep learning classifiers provide the most accurate means of automatically diagnosing diabetic retinopathy (DR) based on optical coherence tomography (OCT) and its angiography (OCTA). The power of these models is attributable in part to the inclusion of hidden layers that provide the complexity required to achieve a desired task. However, hidden layers also render algorithm outputs difficult to interpret. Here we introduce a novel biomarker activation map (BAM) framework based on generative adversarial learning that allows clinicians to verify and understand classifiers decision-making. A data set including 456 macular scans were graded as non-referable or referable DR based on current clinical standards. A DR classifier that was used to evaluate our BAM was first trained based on this data set. The BAM generation framework was designed by combing two U-shaped generators to provide meaningful interpretability to this classifier. The main generator was trained to take referable scans as input and produce an output that would be classified by the classifier as non-referable. The BAM is then constructed as the difference image between the output and input of the main generator. To ensure that the BAM only highlights classifier-utilized biomarkers an assistant generator was trained to do the opposite, producing scans that would be classified as referable by the classifier from non-referable scans. The generated BAMs highlighted known pathologic features including nonperfusion area and retinal fluid. A fully interpretable classifier based on these highlights could help clinicians better utilize and verify automated DR diagnosis.