用于估计模型不确定性的线性拉普拉斯方法在贝叶斯深度学习社区中引起了人们的重新关注。该方法提供了可靠的误差线,并接受模型证据的封闭式表达式,从而可以选择模型超参数。在这项工作中,我们检查了这种方法背后的假设,尤其是与模型选择结合在一起。我们表明,这些与一些深度学习的标准工具(构成近似方法和归一化层)相互作用,并为如何更好地适应这种经典方法对现代环境提出建议。我们为我们的建议提供理论支持,并在MLP,经典CNN,具有正常化层,生成性自动编码器和变压器的剩余网络上进行经验验证它们。
translated by 谷歌翻译
Farquhar等人。[2021]表明,纠正具有协议式模型的主动学习偏差导致下游性能提高。然而,对于诸如NNS的过度指数化模型,然而,校正导致减少或不变的性能。他们认为这是由于“过度装备偏见”,其抵消了主动学习偏差。我们表明深度不确定性网络在低过度装备制度中运行,就像顺相位表一样。因此,它们应该看到具有偏差校正的性能的增加。令人惊讶的是,他们没有。我们建议这种负面结果以及结果Farquhar等。[2021]可以通过普遍化误差的偏差差异分解的镜头来解释。
translated by 谷歌翻译
在主动学习中,训练数据集的大小和复杂性随时间而变化。随着更多要点,由主动学习开始时可用的数据量良好的简单模型可能会受到偏见的影响。可能非常适合于完整数据集的灵活模型可能会在积极学习开始时受到过度装备。我们使用深度不确定性网络(DUNS)来解决这个问题,其中一个BNN变体,其中网络的深度以及其复杂性。我们发现DUNS在几个活跃的学习任务上表现出其他BNN变体。重要的是,我们表明,在DUNs表现最佳的任务上,它们呈现出比基线的显着不太容易。
translated by 谷歌翻译
最近,深度学习中的不确定性估计已成为提高安全至关重要应用的可靠性和鲁棒性的关键领域。尽管有许多提出的方法要么关注距离感知模型的不确定性,要么是分布式检测的不确定性,要么是针对分布校准的输入依赖性标签不确定性,但这两种类型的不确定性通常都是必要的。在这项工作中,我们提出了用于共同建模模型和数据不确定性的HETSNGP方法。我们表明,我们提出的模型在这两种类型的不确定性之间提供了有利的组合,因此在包括CIFAR-100C,ImagEnet-C和Imagenet-A在内的一些具有挑战性的分发数据集上优于基线方法。此外,我们提出了HETSNGP Ensemble,这是我们方法的结合版本,该版本还对网络参数的不确定性进行建模,并优于其他集合基线。
translated by 谷歌翻译
贝叶斯范式有可能解决深度神经网络的核心问题,如校准和数据效率低差。唉,缩放贝叶斯推理到大量的空间通常需要限制近似。在这项工作中,我们表明它足以通过模型权重的小子集进行推动,以便获得准确的预测后断。另一个权重被保存为点估计。该子网推断框架使我们能够在这些子集上使用表现力,否则难以相容的后近近似。特别是,我们将子网线性化LAPLACE作为一种简单,可扩展的贝叶斯深度学习方法:我们首先使用线性化的拉普拉斯近似来获得所有重量的地图估计,然后在子网上推断出全协方差高斯后面。我们提出了一个子网选择策略,旨在最大限度地保护模型的预测性不确定性。经验上,我们的方法对整个网络的集合和较少的表达后近似进行了比较。
translated by 谷歌翻译
Designing experiments often requires balancing between learning about the true treatment effects and earning from allocating more samples to the superior treatment. While optimal algorithms for the Multi-Armed Bandit Problem (MABP) provide allocation policies that optimally balance learning and earning, they tend to be computationally expensive. The Gittins Index (GI) is a solution to the MABP that can simultaneously attain optimality and computationally efficiency goals, and it has been recently used in experiments with Bernoulli and Gaussian rewards. For the first time, we present a modification of the GI rule that can be used in experiments with exponentially-distributed rewards. We report its performance in simulated 2- armed and 3-armed experiments. Compared to traditional non-adaptive designs, our novel GI modified design shows operating characteristics comparable in learning (e.g. statistical power) but substantially better in earning (e.g. direct benefits). This illustrates the potential that designs using a GI approach to allocate participants have to improve participant benefits, increase efficiencies, and reduce experimental costs in adaptive multi-armed experiments with exponential rewards.
translated by 谷歌翻译
We introduce Argoverse 2 (AV2) - a collection of three datasets for perception and forecasting research in the self-driving domain. The annotated Sensor Dataset contains 1,000 sequences of multimodal data, encompassing high-resolution imagery from seven ring cameras, and two stereo cameras in addition to lidar point clouds, and 6-DOF map-aligned pose. Sequences contain 3D cuboid annotations for 26 object categories, all of which are sufficiently-sampled to support training and evaluation of 3D perception models. The Lidar Dataset contains 20,000 sequences of unlabeled lidar point clouds and map-aligned pose. This dataset is the largest ever collection of lidar sensor data and supports self-supervised learning and the emerging task of point cloud forecasting. Finally, the Motion Forecasting Dataset contains 250,000 scenarios mined for interesting and challenging interactions between the autonomous vehicle and other actors in each local scene. Models are tasked with the prediction of future motion for "scored actors" in each scenario and are provided with track histories that capture object location, heading, velocity, and category. In all three datasets, each scenario contains its own HD Map with 3D lane and crosswalk geometry - sourced from data captured in six distinct cities. We believe these datasets will support new and existing machine learning research problems in ways that existing datasets do not. All datasets are released under the CC BY-NC-SA 4.0 license.
translated by 谷歌翻译
Extracting complex structures from grid-based data is a common key step in automated medical image analysis. The conventional solution to recovering tree-structured geometries typically involves computing the minimal cost path through intermediate representations derived from segmentation masks. However, this methodology has significant limitations in the context of projective imaging of tree-structured 3D anatomical data such as coronary arteries, since there are often overlapping branches in the 2D projection. In this work, we propose a novel approach to predicting tree connectivity structure which reformulates the task as an optimization problem over individual steps of a recursive process. We design and train a two-stage model which leverages the UNet and Transformer architectures and introduces an image-based prompting technique. Our proposed method achieves compelling results on a pair of synthetic datasets, and outperforms a shortest-path baseline.
translated by 谷歌翻译
Cashews are grown by over 3 million smallholders in more than 40 countries worldwide as a principal source of income. As the third largest cashew producer in Africa, Benin has nearly 200,000 smallholder cashew growers contributing 15% of the country's national export earnings. However, a lack of information on where and how cashew trees grow across the country hinders decision-making that could support increased cashew production and poverty alleviation. By leveraging 2.4-m Planet Basemaps and 0.5-m aerial imagery, newly developed deep learning algorithms, and large-scale ground truth datasets, we successfully produced the first national map of cashew in Benin and characterized the expansion of cashew plantations between 2015 and 2021. In particular, we developed a SpatioTemporal Classification with Attention (STCA) model to map the distribution of cashew plantations, which can fully capture texture information from discriminative time steps during a growing season. We further developed a Clustering Augmented Self-supervised Temporal Classification (CASTC) model to distinguish high-density versus low-density cashew plantations by automatic feature extraction and optimized clustering. Results show that the STCA model has an overall accuracy of 80% and the CASTC model achieved an overall accuracy of 77.9%. We found that the cashew area in Benin has doubled from 2015 to 2021 with 60% of new plantation development coming from cropland or fallow land, while encroachment of cashew plantations into protected areas has increased by 70%. Only half of cashew plantations were high-density in 2021, suggesting high potential for intensification. Our study illustrates the power of combining high-resolution remote sensing imagery and state-of-the-art deep learning algorithms to better understand tree crops in the heterogeneous smallholder landscape.
translated by 谷歌翻译
Grasping is an incredible ability of animals using their arms and limbs in their daily life. The human hand is an especially astonishing multi-fingered tool for precise grasping, which helped humans to develop the modern world. The implementation of the human grasp to virtual reality and telerobotics is always interesting and challenging at the same time. In this work, authors surveyed, studied, and analyzed the human hand-grasping behavior for the possibilities of haptic grasping in the virtual and remote environment. This work is focused on the motion and force analysis of fingers in human hand grasping scenarios and the paper describes the transition of the human hand grasping towards a tripod haptic grasp model for effective interaction in virtual reality.
translated by 谷歌翻译