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Facebook AI Open-Sources PyTorch-BigGraph Tool for 'Extremely Large' Graphs

#artificialintelligence

Facebook AI Research has announced it is open-sourcing PyTorch-BigGraph (PBG), a tool that can easily process and produce graph embeddings for extremely large graphs. PBG can also process multi-relation graph embeddings where a model is too large to fit in memory. Facebook boasts that PBG not only performs faster than commonly-used embedding softwares, but also provides higher-quality results compared with state-of-the-art benchmarks. The company says PBG will allow users to quickly produce high-quality embeddings from a large graph using either a single machine or multiple machines in parallel. Graphs are widely used in almost all types of programming for representing data.


Artificial intelligence may have a bigger presence in future space missions

#artificialintelligence

What they did: The SDO instrument in question is known as MEGS-A, and it was designed to keep an eye on ultraviolet radiation levels, which correlate with a ballooning of the Earth's outer atmosphere that can harm satellites in near-Earth orbit. A deep-learning network that researchers at NASA Frontier Development Lab created with help from IBM, SETI, and Nimbix in 2018 may soon replace the failed instrument by inferring what ultraviolet radiation levels that instrument would detect based on what the other instruments on SDO are observing at any given time, NASA AI consultant Graham Mackintosh tells Axios. While NASA isn't yet using the fix operationally, the results are promising, Mackintosh added. What to watch: AI models like this could also be used for other future missions, Mackintosh said. Instead of loading 3 instruments on a satellite to measure different aspects of the space environment, you could potentially launch two and use the data collected to infer the information that would have been measured by a third.


Analysis of the Gradient Descent Algorithm for a Deep Neural Network Model with Skip-connections

arXiv.org Machine Learning

The behavior of the gradient descent (GD) algorithm is analyzed for a deep neural network model with skip-connections. It is proved that in the over-parametrized regime, for a suitable initialization, with high probability GD can find a global minimum exponentially fast. Generalization error estimates along the GD path are also established. As a consequence, it is shown that when the target function is in the reproducing kernel Hilbert space (RKHS) with a kernel defined by the initialization, there exist generalizable early-stopping solutions along the GD path. In addition, it is also shown that the GD path is uniformly close to the functions given by the related random feature model. Consequently, in this "implicit regularization" setting, the deep neural network model deteriorates to a random feature model. Our results hold for neural networks of any width larger than the input dimension.


Pre-training of Context-aware Item Representation for Next Basket Recommendation

arXiv.org Machine Learning

Next basket recommendation, which aims to predict the next a few items that a user most probably purchases given his historical transactions, plays a vital role in market basket analysis. From the viewpoint of item, an item could be purchased by different users together with different items, for different reasons. Therefore, an ideal recommender system should represent an item considering its transaction contexts. Existing state-of-the-art deep learning methods usually adopt the static item representations, which are invariant among all of the transactions and thus cannot achieve the full potentials of deep learning. Inspired by the pre-trained representations of BERT in natural language processing, we propose to conduct context-aware item representation for next basket recommendation, called Item Encoder Representations from Transformers (IERT). In the offline phase, IERT pre-trains deep item representations conditioning on their transaction contexts. In the online recommendation phase, the pre-trained model is further fine-tuned with an additional output layer. The output contextualized item embeddings are used to capture users' sequential behaviors and general tastes to conduct recommendation. Experimental results on the Ta-Feng data set show that IERT outperforms the state-of-the-art baseline methods, which demonstrated the effectiveness of IERT in next basket representation.


Dot-to-Dot: Achieving Structured Robotic Manipulation through Hierarchical Reinforcement Learning

arXiv.org Artificial Intelligence

Robotic systems are ever more capable of automation and fulfilment of complex tasks, particularly with reliance on recent advances in intelligent systems, deep learning and artificial intelligence in general. However, as robots and humans come closer together in their interactions, the matter of interpretability, or explainability of robot decision-making processes for the human grows in importance. A successful interaction and collaboration would only be possible through mutual understanding of underlying representations of the environment and the task at hand. This is currently a challenge in deep learning systems. We present a hierarchical deep reinforcement learning system, consisting of a low-level agent handling the large actions/states space of a robotic system efficiently, by following the directives of a high-level agent which is learning the high-level dynamics of the environment and task. This high-level agent forms a representation of the world and task at hand that is interpretable for a human operator. The method, which we call Dot-to-Dot, is tested on a MuJoCo-based model of the Fetch Robotics Manipulator, as well as a Shadow Hand, to test its performance. Results show efficient learning of complex actions/states spaces by the low-level agent, and an interpretable representation of the task and decision-making process learned by the high-level agent.


Random Projection in Neural Episodic Control

arXiv.org Artificial Intelligence

End-to-end deep reinforcement learning has enabled agents to learn with little preprocessing by humans. However, it is still difficult to learn stably and efficiently because the learning method usually uses a nonlinear function approximation. Neural Episodic Control (NEC), which has been proposed in order to improve sample efficiency, is able to learn stably by estimating action values using a non-parametric method. In this paper, we propose an architecture that incorporates random projection into NEC to train with more stability. In addition, we verify the effectiveness of our architecture by Atari's five games. The main idea is to reduce the number of parameters that have to learn by replacing neural networks with random projection in order to reduce dimensions while keeping the learning end-to-end.


Attribute-Guided Sketch Generation

arXiv.org Artificial Intelligence

-- Facial attributes are important since they provide a detailed description and determine the visual appearance of human faces. In this paper, we aim at converting a face image to a sketch while simultaneously generating facial attributes. T o this end, we propose a novel Attribute-Guided Sketch Generative Adversarial Network (ASGAN) which is an end-to-end framework and contains two pairs of generators and discriminators, one of which is used to generate faces with attributes while the other one is employed for image-to-sketch translation. The two generators form a W-shaped network (W-net) and they are trained jointly with a weight-sharing constraint. Additionally, we also propose two novel discriminators, the residual one focusing on attribute generation and the triplex one helping to generate realistic looking sketches. T o validate our model, we have created a new large dataset with 8,804 images, named the Attribute Face Photo & Sketch (AFPS) dataset which is the first dataset containing attributes associated to face sketch images. The experimental results demonstrate that the proposed network (i) generates more photo-realistic faces with sharper facial attributes than baselines and (ii) has good generalization capability on different generative tasks. Recently, there has been a new trend in computer vision to use machines to express the "creativity" of art. Novel and never-seen-before images can be generated by inverting the convolution process in CNN ("upconvolution" or "deconvolution"), which gives such networks the ability to "dream" [23] and to generate images.


SpeechYOLO: Detection and Localization of Speech Objects

arXiv.org Machine Learning

In this paper, we propose to apply object detection methods from the vision domain on the speech recognition domain, by treating audio fragments as objects. More specifically, we present SpeechYOLO, which is inspired by the YOLO algorithm for object detection in images. The goal of SpeechYOLO is to localize boundaries of utterances within the input signal, and to correctly classify them. Our system is composed of a convolutional neural network, with a simple least-mean-squares loss function. We evaluated the system on several keyword spotting tasks, that include corpora of read speech and spontaneous speech. Our system compares favorably with other algorithms trained for both localization and classification.


Learning Spatiotemporal Features of Ride-sourcing Services with Fusion Convolutional Network

arXiv.org Machine Learning

In order to collectively forecast the demand of ride-sourcing services in all regions of a city, convolutional neural networks (CNNs) have been applied with commendable results. However, local statistical differences throughout the geographical layout of the city make the spatial stationarity assumption of the convolution invalid, which limits the performance of CNNs on demand forecasting task. Hence, we propose a novel deep learning framework called LC-ST-FCN (locally-connected spatiotemporal fully-convolutional neural network) that consists of a stack of 3D convolutional layers, 2D (standard) convolutional layers, and locally connected convolutional layers. This fully convolutional architecture maintains the spatial coordinates of the input and no spatial information is lost between layers. Features are fused across layers to define a tunable nonlinear local-to-global-to-local representation, where both global and local statistics can be learned to improve predictive performance. Furthermore, as the local statistics vary from region to region, the arithmetic-mean-based metrics frequently used in spatial stationarity situations cannot effectively evaluate the models. We propose a weighted-arithmetic approach to deal with this situation. In the experiments, a real dataset from a ride-sourcing service platform (DiDiChuxing) is used, which demonstrates the effectiveness and superiority of our proposed model and evaluation method.


Should I Raise The Red Flag? A comprehensive survey of anomaly scoring methods toward mitigating false alarms

arXiv.org Machine Learning

A general Intrusion Detection System (IDS) fundamentally acts based on an Anomaly Detection System (ADS) or a combination of anomaly detection and signature-based methods, gathering and analyzing observations and reporting possible suspicious cases to a system administrator or the other users for further investigation. One of the notorious challenges which even the state-of-the-art ADS and IDS have not overcome is the possibility of a very high false alarms rate. Especially in very large and complex system settings, the amount of low-level alarms easily overwhelms administrators and increases their tendency to ignore alerts. We can group the existing false alarm mitigation strategies into two main families: The first group covers the methods directly customized and applied toward higher quality anomaly scoring in ADS. The second group includes approaches utilized in the related contexts as a filtering method toward decreasing the possibility of false alarm rates. Given the lack of a comprehensive study regarding possible ways to mitigate the false alarm rates, in this paper, we review the existing techniques for false alarm mitigation in ADS and present the pros and cons of each technique. We also study a few promising techniques applied in the signature-based IDS and other related contexts like commercial Security Information and Event Management (SIEM) tools, which are applicable and promising in the ADS context. Finally, we conclude with some directions for future research.