In recent years, surrogate models have been successfully used in likelihood-free inference to decrease the number of simulator evaluations. The current state-of-the-art performance for this task has been achieved by Bayesian Optimization with Gaussian Processes (GPs). While this combination works well for unimodal target distributions, it is restricting the flexibility and applicability of Bayesian Optimization for accelerating likelihood-free inference more generally. We address this problem by proposing a Deep Gaussian Process (DGP) surrogate model that can handle more irregularly behaved target distributions. Our experiments show how DGPs can outperform GPs on objective functions with multimodal distributions and maintain a comparable performance in unimodal cases. This confirms that DGPs as surrogate models can extend the applicability of Bayesian Optimization for likelihood-free inference (BOLFI), while adding computational overhead that remains negligible for computationally intensive simulators.

Sony and Guerrilla Games tentatively plan to release Horizon Forbidden West sometime next year. In a new video detailing the upcoming open-world title, game director Mathijs de Jonge, said the studio "aims" to release the game in 2021. That means Forbidden West won't make the PlayStation 5's 2020 holiday launch. Outside of a release date, the three-minute video is full of tantalizing details. According to de Jonge, the game's title refers to a "mysterious new frontier" extending from Utah to the Pacific Ocean.

Seismic wave data has revealed giant structures 2900 kilometres beneath the surface of Earth, at the boundary between Earth's molten core and solid mantle. The structure, known as an ultra-low velocity (ULV) zone, is about 1000 kilometres in diameter and 25 kilometres thick, says Kim. These structures are called ULV zones because seismic waves pass through them at slower velocities, but what they are made of is still a mystery. They might be chemically distinct from Earth's iron–nickel alloy core and silicate rock mantle, or have different thermal properties. The researchers discovered the structure while analysing 7000 records of seismic activity from earthquakes that occurred around the Pacific Ocean basin between 1990 and 2018.

We propose a hierarchical learning strategy aimed at generating sparse representations and associated models for large noisy datasets. The hierarchy follows from approximation spaces identified at successively finer scales. For promoting model generalization at each scale, we also introduce a novel, projection based penalty operator across multiple dimension, using permutation operators for incorporating proximity and ordering information. The paper presents a detailed analysis of approximation properties in the reconstruction Reproducing Kernel Hilbert Spaces (RKHS) with emphasis on optimality and consistency of predictions and behavior of error functionals associated with the produced sparse representations. Results show the performance of the approach as a data reduction and modeling strategy on both synthetic (univariate and multivariate) and real datasets (time series). The sparse model for the test datasets, generated by the presented approach, is also shown to efficiently reconstruct the underlying process and preserve generalizability.

Dr. Albert Hsiao and his colleagues at the University of California-San Diego health system had been working for 18 months on an artificial intelligence program designed to help doctors identify pneumonia on a chest X-ray. When the coronavirus hit the United States, they decided to see what it could do. His team is one of several around the country that has pushed AI programs developed in a calmer time into the COVID-19 crisis to perform tasks like deciding which patients face the greatest risk of complications and which can be safely channeled into lower-intensity care. The machine-learning programs scroll through millions of pieces of data to detect patterns that may be hard for clinicians to discern. Yet few of the algorithms have been rigorously tested against standard procedures.

One of the most pressing questions public health officials are trying to answer about the coronavirus is how many people actually have been infected by it. Have a relatively significant portion of Californians been infected with the virus but survived without much problem? Or has the virus touched only a tiny sliver of California, suggesting the chances of serious illness are greater if you're infected? In April, controversial studies out of Stanford University and USC suggested the coronavirus has circulated much more widely than previously thought in Silicon Valley and Los Angeles County. Almost immediately, there have been questions from other epidemiologists around the country about whether those estimates were too high.

Dr. Albert Hsiao and his colleagues at the University of California–San Diego health system had been working for 18 months on an artificial intelligence program designed to help doctors identify pneumonia on a chest X-ray. When the coronavirus hit the United States, they decided to see what it could do. The researchers quickly deployed the application, which dots X-ray images with spots of color where there may be lung damage or other signs of pneumonia. It has now been applied to more than 6,000 chest X-rays, and it's providing some value in diagnosis, said Hsiao, the director of UCSD's augmented imaging and artificial intelligence data analytics laboratory. His team is one of several around the country that has pushed AI programs developed in a calmer time into the COVID-19 crisis to perform tasks like deciding which patients face the greatest risk of complications and which can be safely channeled into lower-intensity care.

It is proposed to use analogs of the forecast mean to generate an ensemble of perturbations for use in ensemble optimal interpolation (EnOI) or ensemble variational (EnVar) methods. A new method of constructing analogs using variational autoencoders (VAEs; a machine learning method) is proposed. The resulting analog methods using analogs from a catalog (AnEnOI), and using constructed analogs (cAnEnOI), are tested in the context of a multiscale Lorenz-`96 model, with standard EnOI and an ensemble square root filter for comparison. The use of analogs from a modestly-sized catalog is shown to improve the performance of EnOI, with limited marginal improvements resulting from increases in the catalog size. The method using constructed analogs (cAnEnOI) is found to perform as well as a full ensemble square root filter, and to be robust over a wide range of tuning parameters.

You may even be using one to read this article. Wi-Fi has become essential to our personal and professional lives. The smartphone and the internet we use today wouldn't have been possible without wireless communication technologies such as Wi-Fi. In 1995 if you wanted to "surf" the internet at home, you had to chain yourself to a network cable like it was an extension cord. In 1997, Wi-Fi was invented and released for consumer use.

Waymo's plan to resume self-driving operations will soon extend to San Francisco. A spokesperson has confirmed a report in The Verge that Waymo's autonomous minivans will return to San Francisco Bay Area streets on June 8th. It will instead carry out "charitable delivery support to community partners," according to the spokesperson. The original report said these would include art kit deliveries for local children as well as services for LightHouse for the Blind and Visually Impaired. According to the leaked email from Waymo partner Transdev, the resumption will involve gradually ramping up the number of vehicle operators (no more than one per van) while enforcing a "wealth of safety measures and training" that include temperature checks.