The receptive field (RF), which determines the region of time series to be ``seen'' and used, is critical to improve the performance for time series classification (TSC). However, the variation of signal scales across and within time series data, makes it challenging to decide on proper RF sizes for TSC. In this paper, we propose a dynamic sparse network (DSN) with sparse connections for TSC, which can learn to cover various RF without cumbersome hyper-parameters tuning. The kernels in each sparse layer are sparse and can be explored under the constraint regions by dynamic sparse training, which makes it possible to reduce the resource cost. The experimental results show that the proposed DSN model can achieve state-of-art performance on both univariate and multivariate TSC datasets with less than 50\% computational cost compared with recent baseline methods, opening the path towards more accurate resource-aware methods for time series analyses. Our code is publicly available at: https://github.com/QiaoXiao7282/DSN.
translated by 谷歌翻译
Recent works have impressively demonstrated that there exists a subnetwork in randomly initialized convolutional neural networks (CNNs) that can match the performance of the fully trained dense networks at initialization, without any optimization of the weights of the network (i.e., untrained networks). However, the presence of such untrained subnetworks in graph neural networks (GNNs) still remains mysterious. In this paper we carry out the first-of-its-kind exploration of discovering matching untrained GNNs. With sparsity as the core tool, we can find \textit{untrained sparse subnetworks} at the initialization, that can match the performance of \textit{fully trained dense} GNNs. Besides this already encouraging finding of comparable performance, we show that the found untrained subnetworks can substantially mitigate the GNN over-smoothing problem, hence becoming a powerful tool to enable deeper GNNs without bells and whistles. We also observe that such sparse untrained subnetworks have appealing performance in out-of-distribution detection and robustness of input perturbations. We evaluate our method across widely-used GNN architectures on various popular datasets including the Open Graph Benchmark (OGB).
translated by 谷歌翻译
检测数据分布突然变化的变更点检测(CPD)被认为是时间序列分析中最重要的任务之一。尽管关于离线CPD的文献广泛,但无监督的在线CPD仍面临主要挑战,包括可扩展性,超参数调整和学习限制。为了减轻其中一些挑战,在本文中,我们提出了一种新颖的深度学习方法,用于从多维时间序列中无监督的在线CPD,名为Adaptive LSTM-AUTOENOCODER变更点检测(ALACPD)。 ALACPD利用了基于LSTM-AutoEncoder的神经网络来执行无监督的在线CPD。它连续地适应了传入的样本,而无需保留先前接收的输入,因此没有内存。我们对几个实际时间序列的CPD基准进行了广泛的评估。我们表明,在时间序列细分的质量方面,ALACPD平均在最先进的CPD算法中排名第一,并且就估计更改点的准确性而言,它与表现最好。 ALACPD的实现可在Github \ footNote {\ url {https://github.com/zahraatashgahi/alacpd}}上在线获得。
translated by 谷歌翻译
关于稀疏神经网络训练(稀疏训练)的最新研究表明,通过从头开始训练本质上稀疏的神经网络可以实现绩效和效率之间的令人信服的权衡。现有的稀疏训练方法通常努力在一次跑步中找到最佳的稀疏子网,而无需涉及任何昂贵的密集或预训练步骤。例如,作为最突出的方向之一,动态稀疏训练(DST)能够通过在训练过程中迭代发展稀疏拓扑来实现竞争性训练的竞争性能。在本文中,我们认为最好分配有限的资源来创建多个低损失的稀疏子网并将其超级置于更强的基因,而不是完全分配所有资源以找到单个子网络。为了实现这一目标,需要两个Desiderata:(1)在一个培训过程中有效生产许多低损失的子网,即所谓的廉价门票,仅限于用于密集培训的标准培训时间; (2)将这些廉价的门票有效地超级为一个更强的子网,而无需超越约束参数预算。为了证实我们的猜想,我们提出了一种新颖的稀疏训练方法,称为\ textbf {sup-tickets},可以在单个稀疏到较小的训练过程中同时满足上述两个desiderata。在CIFAR-10/100和Imagenet上的各种现代体系结构中,我们表明,SUP-Tickets与现有的稀疏训练方法无缝集成,并显示出一致的性能提高。
translated by 谷歌翻译
在持续学习中使用神经网络中的任务特定组件(CL)是一种令人信服的策略,可以解决固定容量模型中稳定性 - 塑性困境,而无需访问过去的数据。当前方法仅着重于选择一个新任务的子网络,以减少忘记过去任务。但是,这种选择可能会限制有助于将来学习的相关过去知识的前瞻性转移。我们的研究表明,当统一的分类器用于所有类别的任务课程学习(class-il)时,共同满足这两个目标是更具挑战性的,因为这很容易跨越任务之间的类之间的歧义。此外,当跨任务的课程相似性增加时,挑战就会增加。为了应对这一挑战,我们提出了一种名为AFAF的新CL方法,旨在避免忘记并允许使用Fix-apainality模型在IL类中向前转移。 AFAF分配了一个子网络,该子网络可以选择性地转移相关知识到新任务,同时保留过去的知识,重复一些先前分配的组件以利用固定容量,并在存在相似之处时解决类型。该实验表明,AFAF在为模型提供多种CL所需属性方面的有效性,同时在具有不同语义相似性的各种具有挑战性的基准上优于最先进的方法。
translated by 谷歌翻译
最近对稀疏神经网络的作品已经证明了独立从头开始训练稀疏子网,以匹配其相应密集网络的性能。然而,识别这种稀疏的子网(获奖票)涉及昂贵的迭代火车 - 培训 - 培训过程(例如,彩票票证假设)或过度扩展的训练时间(例如,动态稀疏训练)。在这项工作中,我们在稀疏神经网络训练和深度合并技术之间汲取了独特的联系,产生了一个名为FreeTickets的新型集合学习框架。 FreeTickets而不是从密集的网络开始,随机初始化稀疏的子网,然后在动态调整其稀疏掩码的同时列举子网,从而在整个训练过程中产生许多不同的稀疏子网。 FreeTickets被定义为这些稀疏子网的集合,在这种单次通过,稀疏稀疏训练中自由获得,其仅使用Vanilla密集培训所需的计算资源的一小部分。此外,尽管是模型的集合,但与单一密集模型相比,FreeTickets的参数和训练拖鞋更少:这种看似反向直观的结果是由于每个子网的高稀疏性。与标准致密基线相比,观察到惯性基因术,以预测准确性,不确定度估计,鲁棒性和效率相比表现出显着的全面改进。 FreeTickets在ImageNet上只使用后者所需的四分之一的培训拖鞋,可以轻松地表达Naive Deep EndleBe。我们的结果提供了对稀疏神经网络的强度的见解,并表明稀疏性的好处超出了通常预期的推理效率。
translated by 谷歌翻译
最近,稀疏的培训方法已开始作为事实上的人工神经网络的培训和推理效率的方法。然而,这种效率只是理论上。在实践中,每个人都使用二进制掩码来模拟稀疏性,因为典型的深度学习软件和硬件已针对密集的矩阵操作进行了优化。在本文中,我们采用正交方法,我们表明我们可以训练真正稀疏的神经网络以收获其全部潜力。为了实现这一目标,我们介绍了三个新颖的贡献,这些贡献是专门为稀疏神经网络设计的:(1)平行训练算法及其相应的稀疏实现,(2)具有不可训练的参数的激活功能,以支持梯度流动,以支持梯度流量, (3)隐藏的神经元对消除冗余的重要性指标。总而言之,我们能够打破记录并训练有史以来最大的神经网络在代表力方面训练 - 达到蝙蝠大脑的大小。结果表明,我们的方法具有最先进的表现,同时为环保人工智能时代开辟了道路。
translated by 谷歌翻译
Sparse neural networks attract increasing interest as they exhibit comparable performance to their dense counterparts while being computationally efficient. Pruning the dense neural networks is among the most widely used methods to obtain a sparse neural network. Driven by the high training cost of such methods that can be unaffordable for a low-resource device, training sparse neural networks sparsely from scratch has recently gained attention. However, existing sparse training algorithms suffer from various issues, including poor performance in high sparsity scenarios, computing dense gradient information during training, or pure random topology search. In this paper, inspired by the evolution of the biological brain and the Hebbian learning theory, we present a new sparse training approach that evolves sparse neural networks according to the behavior of neurons in the network. Concretely, by exploiting the cosine similarity metric to measure the importance of the connections, our proposed method, Cosine similarity-based and Random Topology Exploration (CTRE), evolves the topology of sparse neural networks by adding the most important connections to the network without calculating dense gradient in the backward. We carried out different experiments on eight datasets, including tabular, image, and text datasets, and demonstrate that our proposed method outperforms several state-of-the-art sparse training algorithms in extremely sparse neural networks by a large gap. The implementation code is available on https://github.com/zahraatashgahi/CTRE
translated by 谷歌翻译
自视觉变压器(VIT)出现以来,变形金刚在计算机视觉世界中迅速发光。卷积神经网络(CNN)的主要作用似乎受到越来越有效的基于变压器的模型的挑战。最近,几个先进的卷积模型以当地但大量注意机制的驱动的大型内核进行反击,显示出吸引力的性能和效率。尽管其中一个(即Replknet)令人印象深刻地设法将内核大小扩展到31x31,而性能提高,但随着内核大小的持续增长,性能开始饱和,与Swin Transformer等高级VIT的缩放趋势相比。在本文中,我们探讨了训练大于31x31的极端卷积的可能性,并测试是否可以通过策略性地扩大卷积来消除性能差距。这项研究最终是从稀疏性的角度施加极大核的食谱,该核心可以将内核平滑地扩展到61x61,并且性能更好。我们提出了稀疏的大内核网络(SLAK),这是一种纯CNN架构,配备了51x51个核,可以与最先进的层次变压器和现代探测器架构(如Convnext和Repleknet and Replknet and Replknet and Replknet and Replinext and Replknet and Replinext and Convnext and Replentical conternels cor相同或更好在成像网分类以及典型的下游任务上。我们的代码可在此处提供https://github.com/vita-group/slak。
translated by 谷歌翻译
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.
translated by 谷歌翻译