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Ghana vs Uruguay, S Korea vs Portugal predictions: World Cup 2022

Al Jazeera

For the second time in this tournament, 24th-ranked Japan delivered one of the most momentous comebacks in World Cup history by defeating seventh-ranked Spain 2-1. Consequently, four-time champions Germany were eliminated at the group stage of a second straight World Cup, despite a 4-2 victory over Costa Rica. For today's first two matches, Kashef, our artificial intelligence (AI) robot, has analysed more than 200 metrics, including the number of wins, goals scored and FIFA rankings, from matches played over the past century. Prediction: Ghana and Uruguay have met only once before, during the 2010 World Cup in South Africa. After a 1-1 draw between both sides, Ghana went on to lose 2-4 in a penalty shootout.


Cameroon vs Brazil predictions: World Cup 2022

Al Jazeera

Kashef, our artificial intelligence (AI) robot, has been crunching the numbers to predict the results of each game, all the way to the finals. For today's matches, Kashef has analysed more than 200 metrics including the number of wins, goals scored, FIFA rankings and more, from matches played over the past century. Prediction: Cameroon have everything to play for to stand any chance of progressing through to the round of 16. Unfortunately for them, they will have to beat five-time World Cup champions Brazil, who have already qualified. While Kashef has given the Indomitable Lions only a five percent chance of beating Brazil, a victory is not impossible.


ViTAL: Vision-Based Terrain-Aware Locomotion for Legged Robots

arXiv.org Artificial Intelligence

This work is on vision-based planning strategies for legged robots that separate locomotion planning into foothold selection and pose adaptation. Current pose adaptation strategies optimize the robot's body pose relative to given footholds. If these footholds are not reached, the robot may end up in a state with no reachable safe footholds. Therefore, we present a Vision-Based Terrain-Aware Locomotion (ViTAL) strategy that consists of novel pose adaptation and foothold selection algorithms. ViTAL introduces a different paradigm in pose adaptation that does not optimize the body pose relative to given footholds, but the body pose that maximizes the chances of the legs in reaching safe footholds. ViTAL plans footholds and poses based on skills that characterize the robot's capabilities and its terrain-awareness. We use the 90 kg HyQ and 140 kg HyQReal quadruped robots to validate ViTAL, and show that they are able to climb various obstacles including stairs, gaps, and rough terrains at different speeds and gaits. We compare ViTAL with a baseline strategy that selects the robot pose based on given selected footholds, and show that ViTAL outperforms the baseline.


Progress and Challenges for the Application of Machine Learning for Neglected Tropical Diseases

arXiv.org Artificial Intelligence

Neglected tropical diseases (NTDs) continue to affect the livelihood of individuals in countries in the Southeast Asia and Western Pacific region. These diseases have been long existing and have caused devastating health problems and economic decline to people in low- and middle-income (developing) countries. An estimated 1.7 billion of the world's population suffer one or more NTDs annually, this puts approximately one in five individuals at risk for NTDs. In addition to health and social impact, NTDs inflict significant financial burden to patients, close relatives, and are responsible for billions of dollars lost in revenue from reduced labor productivity in developing countries alone. There is an urgent need to better improve the control and eradication or elimination efforts towards NTDs. This can be achieved by utilizing machine learning tools to better the surveillance, prediction and detection program, and combat NTDs through the discovery of new therapeutics against these pathogens. This review surveys the current application of machine learning tools for NTDs and the challenges to elevate the state-of-the-art of NTDs surveillance, management, and treatment.


A Deep Learning Architecture for Passive Microwave Precipitation Retrievals using CloudSat and GPM Data

arXiv.org Artificial Intelligence

This paper presents an algorithm that relies on a series of dense and deep neural networks for passive microwave retrieval of precipitation. The neural networks learn from coincidences of brightness temperatures from the Global Precipitation Measurement (GPM) Microwave Imager (GMI) with the active precipitating retrievals from the Dual-frequency Precipitation Radar (DPR) onboard GPM as well as those from the {CloudSat} Profiling Radar (CPR). The algorithm first detects the precipitation occurrence and phase and then estimates its rate, while conditioning the results to some key ancillary information including parameters related to cloud microphysical properties. The results indicate that we can reconstruct the DPR rainfall and CPR snowfall with a detection probability of more than 0.95 while the probability of a false alarm remains below 0.08 and 0.03, respectively. Conditioned to the occurrence of precipitation, the unbiased root mean squared error in estimation of rainfall (snowfall) rate using DPR (CPR) data is less than 0.8 (0.1) mm/hr over oceans and land. Beyond methodological developments, comparing the results with ERA5 reanalysis and official GPM products demonstrates that the uncertainty in global satellite snowfall retrievals continues to be large while there is a good agreement among rainfall products. Moreover, the results indicate that CPR active snowfall data can improve passive microwave estimates of global snowfall while the current CPR rainfall retrievals should only be used for detection and not estimation of rates.


Semantics-Preserved Distortion for Personal Privacy Protection in Information Management

arXiv.org Artificial Intelligence

Although machine learning and especially deep learning methods have played an important role in the field of information management, privacy protection is an important and concerning topic in current machine learning models. In information management field, a large number of texts containing personal information are produced by users every day. As the model training on information from users is likely to invade personal privacy, many methods have been proposed to block the learning and memorizing of the sensitive data in raw texts. In this paper, we try to do this more linguistically via distorting the text while preserving the semantics. In practice, we leverage a recently our proposed metric, Neighboring Distribution Divergence, to evaluate the semantic preservation during the distortion. Based on the metric, we propose two frameworks for semantics-preserved distortion, a generative one and a substitutive one. We conduct experiments on named entity recognition, constituency parsing, and machine reading comprehension tasks. Results from our experiments show the plausibility and efficiency of our distortion as a method for personal privacy protection. Moreover, we also evaluate the attribute attack on three privacy-related tasks in the current natural language processing field, and the results show the simplicity and effectiveness of our data-based improvement approach compared to the structural improvement approach. Further, we also investigate the effects of privacy protection in specific medical information management in this work and show that the medical information pre-training model using our approach can effectively reduce the memory of patients and symptoms, which fully demonstrates the practicality of our approach.


Chunk-aware Alignment and Lexical Constraint for Visual Entailment with Natural Language Explanations

arXiv.org Artificial Intelligence

Visual Entailment with natural language explanations aims to infer the relationship between a text-image pair and generate a sentence to explain the decision-making process. Previous methods rely mainly on a pre-trained vision-language model to perform the relation inference and a language model to generate the corresponding explanation. However, the pre-trained vision-language models mainly build token-level alignment between text and image yet ignore the high-level semantic alignment between the phrases (chunks) and visual contents, which is critical for vision-language reasoning. Moreover, the explanation generator based only on the encoded joint representation does not explicitly consider the critical decision-making points of relation inference. Thus the generated explanations are less faithful to visual-language reasoning. To mitigate these problems, we propose a unified Chunk-aware Alignment and Lexical Constraint based method, dubbed as CALeC. It contains a Chunk-aware Semantic Interactor (arr. CSI), a relation inferrer, and a Lexical Constraint-aware Generator (arr. LeCG). Specifically, CSI exploits the sentence structure inherent in language and various image regions to build chunk-aware semantic alignment. Relation inferrer uses an attention-based reasoning network to incorporate the token-level and chunk-level vision-language representations. LeCG utilizes lexical constraints to expressly incorporate the words or chunks focused by the relation inferrer into explanation generation, improving the faithfulness and informativeness of the explanations. We conduct extensive experiments on three datasets, and experimental results indicate that CALeC significantly outperforms other competitor models on inference accuracy and quality of generated explanations.


GitHub - ARM-software/ComputeLibrary: The Compute Library is a set of computer vision and machine learning functions optimised for both Arm CPUs and GPUs using SIMD technologies.

#artificialintelligence

Important From release 22.05: 'master' branch has been replaced with'main' following our inclusive language update, more information here. Important From release 22.08: armv7a with Android build will no longer be tested or maintained. The Compute Library is a collection of low-level machine learning functions optimized for Arm Cortex -A, Arm Neoverse and Arm Mali GPUs architectures. The library provides superior performance to other open source alternatives and immediate support for new Arm technologies e.g. Note: The documentation includes the reference API, changelogs, build guide, contribution guide, errata, etc.


Subspace clustering in high-dimensions: Phase transitions & Statistical-to-Computational gap

arXiv.org Artificial Intelligence

With the growing size of modern data, clustering techniques play an important role in reducing the dimensionality of the features used in modern Machine Learning pipelines. Indeed, in many tasks of interest ranging from DNA sequence analysis to image classification, the relevant features are known to live in a lower-dimensional space (intrinsic dimension) than their raw acquisition format (extrinsic dimension) [1]. In these cases, identifying these features can help saving computational resources while significantly improving on learning performance. But given a corrupted embedding of low-dimensional features in a high-dimensional space, is it always statistically possible to retrieve them? And if yes - how can reconstruction be achieved efficiently in practice? In this manuscript we address these two fundamental questions in a simple model for subspace clustering: a k-cluster Gaussian mixture model with sparse centroids. In this model, the low-dimensional hidden features are given by the sparse centroids, which are embedded in a higher dimensional space and corrupted by additive Gaussian noise. We assume that the number of non-zero components of the centroids as well as the number of samples scales linearly with the dimension of the embedding space. Given a finite sample from the mixture, the goal of the statistician is to cluster the data, i.e. estimate the centroids (or features) as well as possible.


Sub-quadratic Algorithms for Kernel Matrices via Kernel Density Estimation

arXiv.org Artificial Intelligence

Kernel matrices, as well as weighted graphs represented by them, are ubiquitous objects in machine learning, statistics and other related fields. The main drawback of using kernel methods (learning and inference using kernel matrices) is efficiency -- given $n$ input points, most kernel-based algorithms need to materialize the full $n \times n$ kernel matrix before performing any subsequent computation, thus incurring $\Omega(n^2)$ runtime. Breaking this quadratic barrier for various problems has therefore, been a subject of extensive research efforts. We break the quadratic barrier and obtain $\textit{subquadratic}$ time algorithms for several fundamental linear-algebraic and graph processing primitives, including approximating the top eigenvalue and eigenvector, spectral sparsification, solving linear systems, local clustering, low-rank approximation, arboricity estimation and counting weighted triangles. We build on the recent Kernel Density Estimation framework, which (after preprocessing in time subquadratic in $n$) can return estimates of row/column sums of the kernel matrix. In particular, we develop efficient reductions from $\textit{weighted vertex}$ and $\textit{weighted edge sampling}$ on kernel graphs, $\textit{simulating random walks}$ on kernel graphs, and $\textit{importance sampling}$ on matrices to Kernel Density Estimation and show that we can generate samples from these distributions in $\textit{sublinear}$ (in the support of the distribution) time. Our reductions are the central ingredient in each of our applications and we believe they may be of independent interest. We empirically demonstrate the efficacy of our algorithms on low-rank approximation (LRA) and spectral sparsification, where we observe a $\textbf{9x}$ decrease in the number of kernel evaluations over baselines for LRA and a $\textbf{41x}$ reduction in the graph size for spectral sparsification.