社交媒体有可能提供有关紧急情况和突然事件的及时信息。但是，在每天发布的数百万帖子中找到相关信息可能很困难，并且开发数据分析项目通常需要时间和技术技能。这项研究提出了一种为分析社交媒体的灵活支持的方法，尤其是在紧急情况下。引入了可以采用社交媒体分析的不同用例，并讨论了从大量帖子中检索信息的挑战。重点是分析社交媒体帖子中包含的图像和文本，以及一组自动数据处理工具，用于过滤，分类和使用人类的方法来支持数据分析师的内容。这种支持包括配置自动化工具的反馈和建议，以及众包收集公民的投入。通过讨论Crowd4SDG H2020欧洲项目中开发的三个案例研究来验证结果。

洗钱是一个全球性问题，涉及严重重罪（每年1.7-4万亿欧元的收益，如毒品处理，人口贩运或腐败。金融机构部署的反洗钱系统通常包括与监管框架一致的规则。人类调查人员审查警报和报告可疑案件。这种系统患有高​​假阳性率，破坏其有效性并导致高运营成本。我们提出了一种机器学习分类模型，它补充了基于规则的系统，并学会准确地预测警报的风险。我们的模型使用实体的设计功能和属性以基于图形的特征​​的形式表征实体间关系。我们利用时间窗口来构建动态图形，优化时间和空间效率。我们在真实的银行数据集上验证我们的模型，并展示分流模型如何将误报的数量减少80％，同时检测到90％的真实阳性。通过这种方式，我们的模型可以显着改善反洗钱操作。

移动机器人的视觉导航经典通过SLAM加上最佳规划，最近通过实现作为深网络的端到端培训。虽然前者通常仅限于航点计划，但即使在真实的物理环境中已经证明了它们的效率，后一种解决方案最常用于模拟中，但已被证明能够学习更复杂的视觉推理，涉及复杂的语义规则。通过实际机器人在物理环境中导航仍然是一个开放问题。端到端的培训方法仅在模拟中进行了彻底测试，实验涉及实际机器人的实际机器人在简化的实验室条件下限制为罕见的性能评估。在这项工作中，我们对真实物理代理的性能和推理能力进行了深入研究，在模拟中培训并部署到两个不同的物理环境。除了基准测试之外，我们提供了对不同条件下不同代理商培训的泛化能力的见解。我们可视化传感器使用以及不同类型信号的重要性。我们展示了，对于Pointgoal Task，一个代理在各种任务上进行预先培训，并在目标环境的模拟版本上进行微调，可以达到竞争性能，而无需建模任何SIM2重传，即通过直接从仿真部署培训的代理即可一个真正的物理机器人。

由于2017年介绍了变压器架构，因此许多尝试将自我关注范例带入计算机愿景领域。在本文中，我们提出了一种新颖的自我关注模块，可以很容易地集成在几乎每个卷积神经网络中，专门为计算机视觉设计，LHC：本地（多）头通道（自我关注）。 LHC是基于两个主要思想：首先，我们认为在电脑视觉中利用自我关注范式的最佳方式是渠道明智的应用而不是更探索的空间关注，并且卷积不会被引起的注意力替换经常性网络在NLP中;其次，局部方法有可能更好地克服卷积的局限性而不是全球关注。通过LHC-Net，我们设法在着名的FER2013数据集中实现了新的艺术状态，与先前的SOTA相比，在计算成本方面的复杂性和对“宿主”架构的复杂性显着和影响。

机器人社区已经开始严重依赖越来越逼真的3D模拟器，以便在大量数据上进行大规模培训机器人。但是，一旦机器人部署在现实世界中，仿真差距以及现实世界的变化（例如，灯，物体位移）导致错误。在本文中，我们介绍了SIM2Realviz，这是一种视觉分析工具，可以帮助专家了解并减少机器人EGO-POSE估计任务的这种差距，即使用训练型模型估计机器人的位置。 Sim2Realviz显示了给定模型的详细信息以及在模拟和现实世界中的实例的性能。专家可以识别在给定位置影响模型预测的环境差异，并通过与模型假设的直接交互来探索来解决它。我们详细介绍了工具的设计，以及与对平均偏差的回归利用以及如何解决的案例研究以及如何解决，以及模型如何被诸如自行车等地标的消失的扰动。

Computational units in artificial neural networks follow a simplified model of biological neurons. In the biological model, the output signal of a neuron runs down the axon, splits following the many branches at its end, and passes identically to all the downward neurons of the network. Each of the downward neurons will use their copy of this signal as one of many inputs dendrites, integrate them all and fire an output, if above some threshold. In the artificial neural network, this translates to the fact that the nonlinear filtering of the signal is performed in the upward neuron, meaning that in practice the same activation is shared between all the downward neurons that use that signal as their input. Dendrites thus play a passive role. We propose a slightly more complex model for the biological neuron, where dendrites play an active role: the activation in the output of the upward neuron becomes optional, and instead the signals going through each dendrite undergo independent nonlinear filterings, before the linear combination. We implement this new model into a ReLU computational unit and discuss its biological plausibility. We compare this new computational unit with the standard one and describe it from a geometrical point of view. We provide a Keras implementation of this unit into fully connected and convolutional layers and estimate their FLOPs and weights change. We then use these layers in ResNet architectures on CIFAR-10, CIFAR-100, Imagenette, and Imagewoof, obtaining performance improvements over standard ResNets up to 1.73%. Finally, we prove a universal representation theorem for continuous functions on compact sets and show that this new unit has more representational power than its standard counterpart.

Non-linear state-space models, also known as general hidden Markov models, are ubiquitous in statistical machine learning, being the most classical generative models for serial data and sequences in general. The particle-based, rapid incremental smoother PaRIS is a sequential Monte Carlo (SMC) technique allowing for efficient online approximation of expectations of additive functionals under the smoothing distribution in these models. Such expectations appear naturally in several learning contexts, such as likelihood estimation (MLE) and Markov score climbing (MSC). PARIS has linear computational complexity, limited memory requirements and comes with non-asymptotic bounds, convergence results and stability guarantees. Still, being based on self-normalised importance sampling, the PaRIS estimator is biased. Our first contribution is to design a novel additive smoothing algorithm, the Parisian particle Gibbs PPG sampler, which can be viewed as a PaRIS algorithm driven by conditional SMC moves, resulting in bias-reduced estimates of the targeted quantities. We substantiate the PPG algorithm with theoretical results, including new bounds on bias and variance as well as deviation inequalities. Our second contribution is to apply PPG in a learning framework, covering MLE and MSC as special examples. In this context, we establish, under standard assumptions, non-asymptotic bounds highlighting the value of bias reduction and the implicit Rao--Blackwellization of PPG. These are the first non-asymptotic results of this kind in this setting. We illustrate our theoretical results with numerical experiments supporting our claims.

The visual dimension of cities has been a fundamental subject in urban studies, since the pioneering work of scholars such as Sitte, Lynch, Arnheim, and Jacobs. Several decades later, big data and artificial intelligence (AI) are revolutionizing how people move, sense, and interact with cities. This paper reviews the literature on the appearance and function of cities to illustrate how visual information has been used to understand them. A conceptual framework, Urban Visual Intelligence, is introduced to systematically elaborate on how new image data sources and AI techniques are reshaping the way researchers perceive and measure cities, enabling the study of the physical environment and its interactions with socioeconomic environments at various scales. The paper argues that these new approaches enable researchers to revisit the classic urban theories and themes, and potentially help cities create environments that are more in line with human behaviors and aspirations in the digital age.

General nonlinear sieve learnings are classes of nonlinear sieves that can approximate nonlinear functions of high dimensional variables much more flexibly than various linear sieves (or series). This paper considers general nonlinear sieve quasi-likelihood ratio (GN-QLR) based inference on expectation functionals of time series data, where the functionals of interest are based on some nonparametric function that satisfy conditional moment restrictions and are learned using multilayer neural networks. While the asymptotic normality of the estimated functionals depends on some unknown Riesz representer of the functional space, we show that the optimally weighted GN-QLR statistic is asymptotically Chi-square distributed, regardless whether the expectation functional is regular (root-$n$ estimable) or not. This holds when the data are weakly dependent beta-mixing condition. We apply our method to the off-policy evaluation in reinforcement learning, by formulating the Bellman equation into the conditional moment restriction framework, so that we can make inference about the state-specific value functional using the proposed GN-QLR method with time series data. In addition, estimating the averaged partial means and averaged partial derivatives of nonparametric instrumental variables and quantile IV models are also presented as leading examples. Finally, a Monte Carlo study shows the finite sample performance of the procedure

As various city agencies and mobility operators navigate toward innovative mobility solutions, there is a need for strategic flexibility in well-timed investment decisions in the design and timing of mobility service regions, i.e. cast as "real options" (RO). This problem becomes increasingly challenging with multiple interacting RO in such investments. We propose a scalable machine learning based RO framework for multi-period sequential service region design & timing problem for mobility-on-demand services, framed as a Markov decision process with non-stationary stochastic variables. A value function approximation policy from literature uses multi-option least squares Monte Carlo simulation to get a policy value for a set of interdependent investment decisions as deferral options (CR policy). The goal is to determine the optimal selection and timing of a set of zones to include in a service region. However, prior work required explicit enumeration of all possible sequences of investments. To address the combinatorial complexity of such enumeration, we propose a new variant "deep" RO policy using an efficient recurrent neural network (RNN) based ML method (CR-RNN policy) to sample sequences to forego the need for enumeration, making network design & timing policy tractable for large scale implementation. Experiments on multiple service region scenarios in New York City (NYC) shows the proposed policy substantially reduces the overall computational cost (time reduction for RO evaluation of > 90% of total investment sequences is achieved), with zero to near-zero gap compared to the benchmark. A case study of sequential service region design for expansion of MoD services in Brooklyn, NYC show that using the CR-RNN policy to determine optimal RO investment strategy yields a similar performance (0.5% within CR policy value) with significantly reduced computation time (about 5.4 times faster).