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Fast Multivariate Spatio-temporal Analysis via Low Rank Tensor Learning

Neural Information Processing Systems

Accurate and efficient analysis of multivariate spatio-temporal data is critical in climatology, geology, and sociology applications. Existing models usually assume simple inter-dependence among variables, space, and time, and are computationally expensive. We propose a unified low rank tensor learning framework for multivariate spatio-temporal analysis, which can conveniently incorporate different properties in spatio-temporal data, such as spatial clustering and shared structure among variables. We demonstrate how the general framework can be applied to cokriging and forecasting tasks, and develop an efficient greedy algorithm to solve the resulting optimization problem with convergence guarantee. We conduct experiments on both synthetic datasets and real application datasets to demonstrate that our method is not only significantly faster than existing methods but also achieves lower estimation error.


Revealed: What humans will look like in 1,000 years, according to scientists

Daily Mail - Science & tech

Looking back at our primate ancestors, it would be easy to assume that humans today have reached the final chapter of our evolution. However, many scientists believe that the way humans appear today is just the start of the story. Thanks to technology, space travel, and climate change, the world around us is changing faster than ever - and experts believe that humanity will change with it. Now, artificial intelligence (AI) reveals what the humans of the future might look like. With Google's ImageFX AI image generator, MailOnline has used predictions from leading scientists to imagine how the human race might evolve.


Using Convolutional Neural Networks to Recognize Rhythm Stimuli from Electroencephalography Recordings

Neural Information Processing Systems

Electroencephalography (EEG) recordings of rhythm perception might contain enough information to distinguish different rhythm types/genres or even identify the rhythms themselves. We apply convolutional neural networks (CNNs) to analyze and classify EEG data recorded within a rhythm perception study in Kigali, Rwanda which comprises 12 East African and 12 Western rhythmic stimuli - each presented in a loop for 32 seconds to 13 participants. We investigate the impact of the data representation and the pre-processing steps for this classification tasks and compare different network structures. Using CNNs, we are able to recognize individual rhythms from the EEG with a mean classification accuracy of 24.4% (chance level 4.17%) over all subjects by looking at less than three seconds from a single channel. Aggregating predictions for multiple channels, a mean accuracy of up to 50% can be achieved for individual subjects.


Approximating Hierarchical MV-sets for Hierarchical Clustering

Neural Information Processing Systems

The goal of hierarchical clustering is to construct a cluster tree, which can be viewed as the modal structure of a density. For this purpose, we use a convex optimization program that can efficiently estimate a family of hierarchical dense sets in high-dimensional distributions. We further extend existing graph-based methods to approximate the cluster tree of a distribution. By avoiding direct density estimation, our method is able to handle high-dimensional data more efficiently than existing density-based approaches. We present empirical results that demonstrate the superiority of our method over existing ones.


Generalized Higher-Order Orthogonal Iteration for Tensor Decomposition and Completion

Neural Information Processing Systems

Low-rank tensor estimation has been frequently applied in many real-world problems. Despite successful applications, existing Schatten 1-norm minimization (SNM) methods may become very slow or even not applicable for large-scale problems. To address this difficulty, we therefore propose an efficient and scalable core tensor Schatten 1-norm minimization method for simultaneous tensor decomposition and completion, with a much lower computational complexity. We first induce the equivalence relation of Schatten 1-norm of a low-rank tensor and its core tensor. Then the Schatten 1-norm of the core tensor is used to replace that of the whole tensor, which leads to a much smaller-scale matrix SNM problem. Finally, an efficient algorithm with a rank-increasing scheme is developed to solve the proposed problem with a convergence guarantee. Extensive experimental results show that our method is usually more accurate than the state-of-the-art methods, and is orders of magnitude faster.



Here's how to appease your inner child--with his retro game console

Popular Science

If you're dreading the long winter nights, the Kinhank Super Console X2 Pro is here to save the season--and your sanity. With over 70,000 pre-loaded retro games, this gaming emulator console brings back the joy of childhood classics while offering all the modern conveniences you'd expect today. From Pac-Man and Sonic to Dark Souls and Rocket League, you'll find titles spanning generations and genres. It all runs smoothly thanks to the powerful S905X2 chip and the Mali-G31MP2 GPU, delivering stunning 4K UHD visuals for a truly immersive experience. Powered by dual systems, Android 9.0 for streaming and apps, and EmuELEC 4.5 for gaming, the Super Console X2 gives you versatility at your fingertips.



Multitask learning meets tensor factorization: task imputation via convex optimization

Neural Information Processing Systems

We study a multitask learning problem in which each task is parametrized by a weight vector and indexed by a pair of indices, which can be e.g, (consumer, time). The weight vectors can be collected into a tensor and the (multilinear-)rank of the tensor controls the amount of sharing of information among tasks. Two types of convex relaxations have recently been proposed for the tensor multilinear rank. However, we argue that both of them are not optimal in the context of multitask learning in which the dimensions or multilinear rank are typically heterogeneous. We propose a new norm, which we call the scaled latent trace norm and analyze the excess risk of all the three norms. The results apply to various settings including matrix and tensor completion, multitask learning, and multilinear multitask learning. Both the theory and experiments support the advantage of the new norm when the tensor is not equal-sized and we do not a priori know which mode is low rank.