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Modeling the Geospatial Evolution of COVID-19 using Spatio-temporal Convolutional Sequence-to-sequence Neural Networks 基于时空卷积序列到序列神经网络的新冠肺炎地理空间演化模型
IF 1.9 Q1 Mathematics Pub Date : 2021-05-06 DOI: 10.1145/3550272
Mário Cardoso, A. Cavalheiro, Alexandre Borges, A. F. Duarte, A. Soares, M. Pereira, N. Nunes, L. Azevedo, Arlindo L. Oliveira
Europe was hit hard by the COVID-19 pandemic and Portugal was severely affected, having suffered three waves in the first twelve months. Approximately between January 19th and February 5th 2021 Portugal was the country in the world with the largest incidence rate, with 14-day incidence rates per 100,000 inhabitants in excess of 1,000. Despite its importance, accurate prediction of the geospatial evolution of COVID-19 remains a challenge, since existing analytical methods fail to capture the complex dynamics that result from the contagion within a region and the spreading of the infection from infected neighboring regions. We use a previously developed methodology and official municipality level data from the Portuguese Directorate-General for Health (DGS), relative to the first twelve months of the pandemic, to compute an estimate of the incidence rate in each location of mainland Portugal. The resulting sequence of incidence rate maps was then used as a gold standard to test the effectiveness of different approaches in the prediction of the spatial-temporal evolution of the incidence rate. Four different methods were tested: a simple cell level autoregressive moving average (ARMA) model, a cell level vector autoregressive (VAR) model, a municipality-by-municipality compartmental SIRD model followed by direct block sequential simulation, and a new convolutional sequence-to-sequence neural network model based on the STConvS2S architecture. We conclude that the modified convolutional sequence-to-sequence neural network is the best performing method in this task, when compared with the ARMA, VAR, and SIRD models, as well as with the baseline ConvLSTM model.
欧洲受到COVID-19大流行的严重打击,葡萄牙受到严重影响,前12个月经历了三波疫情。大约在2021年1月19日至2月5日期间,葡萄牙是世界上发病率最高的国家,每10万居民的14天发病率超过1000人。尽管具有重要意义,但准确预测COVID-19的地理空间演变仍然是一项挑战,因为现有的分析方法无法捕捉到一个区域内的传染和感染从受感染的邻近区域传播所造成的复杂动态。我们使用以前开发的方法和葡萄牙卫生总局(DGS)的官方市级数据,相对于大流行的前12个月,计算葡萄牙大陆每个地点的发病率估计数。然后将所得的发病率图序列作为金标准来测试不同方法在预测发病率时空演变方面的有效性。测试了四种不同的方法:简单的细胞水平自回归移动平均(ARMA)模型、细胞水平矢量自回归(VAR)模型、逐市划分的SIRD模型,然后进行直接块序列模拟,以及基于STConvS2S架构的新型卷积序列对序列神经网络模型。我们得出结论,与ARMA、VAR和SIRD模型以及基线ConvLSTM模型相比,改进的卷积序列到序列神经网络是该任务中表现最好的方法。
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引用次数: 3
UniTE—The Best of Both Worlds: Unifying Function-fitting and Aggregation-based Approaches to Travel Time and Travel Speed Estimation UniTE——两全其美:统一基于函数拟合和聚合的行程时间和行程速度估计方法
IF 1.9 Q1 Mathematics Pub Date : 2021-04-27 DOI: 10.1145/3517335
T. S. Jepsen, Christian S. Jensen, Thomas D. Nielsen
Travel time and speed estimation are part of many intelligent transportation applications. Existing estimation approaches rely on either function fitting or data aggregation and represent different tradeoffs between generalizability and accuracy. Function-fitting approaches learn functions that map feature vectors of, e.g., routes to travel time or speed estimates, which enables generalization to unseen routes. However, mapping functions are imperfect and offer poor accuracy in practice. Aggregation-based approaches instead form estimates by aggregating historical data, e.g., traversal data for routes. This enables very high accuracy given sufficient data. However, they rely on simplistic heuristics when insufficient data is available, yielding poor generalizability. We present a Unifying approach to Travel time and speed Estimation (UniTE) that combines function-fitting and aggregation-based approaches into a unified framework that aims to achieve the generalizability of function-fitting approaches and the accuracy of aggregation-based approaches when data is available. We demonstrate empirically that an instance of UniTE can improve the accuracies of travel speed and travel time estimation by 40–64% and 3–23%, respectively, compared to using only function fitting or data aggregation.
行程时间和速度估计是许多智能交通应用的一部分。现有的估计方法要么依赖于函数拟合,要么依赖于数据聚合,并在概括性和准确性之间做出了不同的权衡。函数拟合方法学习映射特征向量的函数,例如,将路线映射到旅行时间或速度估计,这可以泛化到看不见的路线。然而,在实际应用中,映射函数并不完善,精度较差。基于聚合的方法通过聚合历史数据(例如,路由的遍历数据)来形成估计。在数据充足的情况下,这可以实现非常高的准确性。然而,当可用的数据不足时,它们依赖于简单的启发式,产生较差的泛化性。我们提出了一种统一的旅行时间和速度估计方法(UniTE),该方法将函数拟合和基于聚合的方法结合到一个统一的框架中,旨在实现函数拟合方法的通用性和基于聚合的方法在数据可用时的准确性。我们的经验证明,与仅使用函数拟合或数据聚合相比,UniTE实例可以将旅行速度和旅行时间的估计精度分别提高40-64%和3-23%。
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引用次数: 2
AIST: An Interpretable Attention-Based Deep Learning Model for Crime Prediction 一种可解释的基于注意的深度学习犯罪预测模型
IF 1.9 Q1 Mathematics Pub Date : 2020-12-16 DOI: 10.1145/3582274
Yeasir Rayhan, T. Hashem
Accuracy and interpretability are two essential properties for a crime prediction model. Accurate prediction of future crime occurrences along with the reason behind a prediction would allow us to plan the crime prevention steps accordingly. The key challenge in developing the model is to capture the non-linear and dynamic spatial dependency and temporal patterns of a specific crime category, while keeping the underlying structure of the model interpretable. In this article, we develop AIST, an Attention-based Interpretable Spatio Temporal Network for crime prediction. AIST models the dynamic spatio-temporal correlations for a crime category based on past crime occurrences, external features (e.g., traffic flow and point of interest information) and recurring trends of crime. Extensive experiments show that AIST outperforms the state-of-the-art techniques in terms of accuracy (e.g., AIST shows a decrease of 4.1% on mean average error and 7.45% on mean square error for the Chicago 2019 crime dataset) and interpretability.1
准确性和可解释性是犯罪预测模型的两个基本属性。准确预测未来的犯罪事件以及预测背后的原因将使我们能够相应地计划预防犯罪的步骤。开发模型的关键挑战是捕捉特定犯罪类别的非线性和动态空间依赖关系和时间模式,同时保持模型的底层结构的可解释性。在本文中,我们开发了一个基于注意力的可解释时空网络,用于犯罪预测。AIST基于过去的犯罪事件、外部特征(如交通流量和兴趣点信息)和犯罪的重复趋势,为犯罪类别建立动态时空相关性模型。大量实验表明,AIST在准确性和可解释性方面优于最先进的技术(例如,AIST显示芝加哥2019年犯罪数据集的平均平均误差降低4.1%,均方误差降低7.45%)
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引用次数: 7
Automatic Deep Inference of Procedural Cities from Global-scale Spatial Data 基于全球尺度空间数据的程序性城市自动深度推理
IF 1.9 Q1 Mathematics Pub Date : 2020-10-27 DOI: 10.1145/3423422
ZhangXiaowei, ShehataAly, BenešBedřich, AliagaDaniel
Recent advances in big spatial data acquisition and deep learning allow novel algorithms that were not possible several years ago. We introduce a novel inverse procedural modeling algorithm for urb...
大空间数据采集和深度学习的最新进展使得几年前不可能实现的新算法成为可能。提出了一种新的逆过程建模算法。
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引用次数: 3
Using Deep Learning for Big Spatial Data Partitioning 深度学习在大空间数据分区中的应用
IF 1.9 Q1 Mathematics Pub Date : 2020-08-12 DOI: 10.1145/3402126
VuTin, BelussiAlberto, MiglioriniSara, EldwayAhmed
This article explores the use of deep learning to choose an appropriate spatial partitioning technique for big data. The exponential increase in the volumes of spatial datasets resulted in the deve...
本文探讨了如何利用深度学习为大数据选择合适的空间划分技术。空间数据集数量的指数级增长导致了…
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引用次数: 9
Quantifying the Effects of Contact Tracing, Testing, and Containment Measures in the Presence of Infection Hotspots 在感染热点地区量化接触者追踪、检测和遏制措施的效果
IF 1.9 Q1 Mathematics Pub Date : 2020-04-15 DOI: 10.1145/3530774
Lars Lorch, Heiner Kremer, W. Trouleau, Stratis Tsirtsis, Aron Szanto, B. Scholkopf, M. Gomez-Rodriguez
Multiple lines of evidence strongly suggest that infection hotspots, where a single individual infects many others, play a key role in the transmission dynamics of COVID-19. However, most of the existing epidemiological models fail to capture this aspect by neither representing the sites visited by individuals explicitly nor characterizing disease transmission as a function of individual mobility patterns. In this work, we introduce a temporal point process modeling framework that specifically represents visits to the sites where individuals get in contact and infect each other. Under our model, the number of infections caused by an infectious individual naturally emerges to be overdispersed. Using an efficient sampling algorithm, we demonstrate how to estimate the transmission rate of infectious individuals at the sites they visit and in their households using Bayesian optimization (BO) and longitudinal case data. Simulations using fine-grained and publicly available demographic data and site locations from Bern, Switzerland showcase the flexibility of our framework. To facilitate research and analyses of other cities and regions, we release an open-source implementation of our framework.
多条证据有力地表明,感染热点在新冠肺炎的传播动态中发挥着关键作用,即单个个体感染许多其他人。然而,大多数现有的流行病学模型既没有明确表示个人访问的地点,也没有将疾病传播描述为个人流动模式的函数,从而未能捕捉到这一方面。在这项工作中,我们引入了一个时间点过程建模框架,该框架专门表示对个人接触并相互感染的地点的访问。在我们的模型下,传染性个体引起的感染数量自然会出现过度分散。使用有效的采样算法,我们演示了如何使用贝叶斯优化(BO)和纵向病例数据来估计感染者在其访问地点和家庭中的传播率。使用来自瑞士伯尔尼的细粒度和公开可用的人口统计数据和站点位置进行的模拟展示了我们框架的灵活性。为了促进对其他城市和地区的研究和分析,我们发布了我们框架的开源实现。
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引用次数: 28
期刊
ACM Transactions on Spatial Algorithms and Systems
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