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AI software scans satellite images and predicts how many residents are overweight

Daily Mail - Science & tech

Scientists have created an AI that can detect obesity from space. The software scans satellite images and predicts how many residents are overweight based on the availability of parks, fast food stores and other buildings in the area. Researchers used deep learning to scan 150,000 high-resolution satellite images from Google Maps in order to identify patterns. They looked at data in six US cities - Bellevue, Seattle, Tacoma, Los Angeles, Memphis, and San Antonio. The team found that features of the built environment explained 64.8 per cent of the variation in obesity between cities.


Artificial intelligence poses a greater challenge to the world than terrorism, top scientist warns

Daily Mail - Science & tech

Artificial intelligence poses a greater challege to the world than terrorism, the incoming president of the British Science Association has warned. Professor Jim Al-Khalili, a physicist at the University of Surrey, warned that progress in artificial intelligence is'happening too fast' and is not being regulated well enough. He said that AI will make Britain increasingly vulnerable to cyber attacks and lead to greater inequality as thousands are rendered unemployed. At a briefing in London ahead of the British Science Festival in Hull this week, he said: 'Until maybe a couple of years ago had I been asked what is the most pressing and important conversation we should be having about our future, I might have said climate change or one of the other big challenges facing humanity, such as terrorism, antimicrobial resistance, the threat of pandemics or world poverty. 'But today I am certain the most important conversation we should be having is about the future of AI.


Flatland: a Lightweight First-Person 2-D Environment for Reinforcement Learning

arXiv.org Machine Learning

Flatland is a simple, lightweight environment for fast prototyping and testing of reinforcement learning agents. It is of lower complexity compared to similar 3D platforms (e.g. DeepMind Lab or VizDoom), but emulates physical properties of the real world, such as continuity, multi-modal partially-observable states with first-person view and coherent physics. We propose to use it as an intermediary benchmark for problems related to Lifelong Learning. Flatland is highly customizable and offers a wide range of task difficulty to extensively evaluate the properties of artificial agents. We experiment with three reinforcement learning baseline agents and show that they can rapidly solve a navigation task in Flatland. A video of an agent acting in Flatland is available here: https://youtu.be/I5y6Y2ZypdA.


Deep Learning Towards Mobile Applications

arXiv.org Artificial Intelligence

Abstract--Recent years have witnessed an explosive growth of mobile devices. Mobile devices are permeating every aspect of our daily lives. With the increasing usage of mobile devices and intelligent applications, there is a soaring demand for mobile applications with machine learning services. Inspired by the tremendous success achieved by deep learning in many machine learning tasks, it becomes a natural trend to push deep learning towards mobile applications. However, there exist many challenges to realize deep learning in mobile applications, including the contradiction between the miniature nature of mobile devices and the resource requirement of deep neural networks, the privacy and security concerns about individuals' data, and so on. To resolve these challenges, during the past few years, great leaps have been made in this area. In this paper, we provide an overview of the current challenges and representative achievements about pushing deep learning on mobile devices from three aspects: training with mobile data, efficient inference on mobile devices, and applications of mobile deep learning. The former two aspects cover the primary tasks of deep learning. Then, we go through our two recent applications that apply the data collected by mobile devices to inferring mood disturbance and user identification. Finally, we conclude this paper with the discussion of the future of this area. The past few years have witnessed an explosive growth of mobile devices which is expected to continue in the next decades. It is predicted that mobile devices will reach 5.6 billion, accounting for 21% of all networked devices in 2020 [1].


Exploring Machine Reading Comprehension with Explicit Knowledge

arXiv.org Artificial Intelligence

To apply general knowledge to machine reading comprehension (MRC), we propose an innovative MRC approach, which consists of a WordNet-based data enrichment method and an MRC model named as Knowledge Aided Reader (KAR). The data enrichment method uses the semantic relations of WordNet to extract semantic level inter-word connections from each passage-question pair in the MRC dataset, and allows us to control the amount of the extraction results by setting a hyper-parameter. KAR uses the extraction results of the data enrichment method as explicit knowledge to assist the prediction of answer spans. According to the experimental results, the single model of KAR achieves an Exact Match (EM) of $72.4$ and an F1 Score of $81.1$ on the development set of SQuAD, and more importantly, by applying different settings in the data enrichment method to change the amount of the extraction results, there is a $2\%$ variation in the resulting performance of KAR, which implies that the explicit knowledge provided by the data enrichment method plays an effective role in the training of KAR.


The LKPY Package for Recommender Systems Experiments: Next-Generation Tools and Lessons Learned from the LensKit Project

arXiv.org Artificial Intelligence

Since 2010, we have built and maintained LensKit, an open-source toolkit for building, researching, and learning about recommender systems. We have successfully used the software in a wide range of recommender systems experiments, to support education in traditional classroom and online settings, and as the algorithmic backend for user-facing recommendation services in movies and books. This experience, along with community feedback, has surfaced a number of challenges with LensKit's design and environmental choices. In response to these challenges, we are developing a new set of tools that leverage the PyData stack to enable the kinds of research experiments and educational experiences that we have been able to deliver with LensKit, along with new experimental structures that the existing code makes difficult. The result is a set of research tools that should significantly increase research velocity and provide much smoother integration with other software such as Keras while maintaining the same level of reproducibility as a LensKit experiment. In this paper, we reflect on the LensKit project, particularly on our experience using it for offline evaluation experiments, and describe the next-generation LKPY tools for enabling new offline evaluations and experiments with flexible, open-ended designs and well-tested evaluation primitives.


Neural-Guided Deductive Search for Real-Time Program Synthesis from Examples

arXiv.org Artificial Intelligence

Synthesizing user-intended programs from a small number of input-output examples is a challenging problem with several important applications like spreadsheet manipulation, data wrangling and code refactoring. Existing synthesis systems either completely rely on deductive logic techniques that are extensively handengineered or on purely statistical models that need massive amounts of data, and in general fail to provide real-time synthesis on challenging benchmarks. In this work, we propose Neural Guided Deductive Search (NGDS), a hybrid synthesis technique that combines the best of both symbolic logic techniques and statistical models. Thus, it produces programs that satisfy the provided specifications by construction and generalize well on unseen examples, similar to data-driven systems. Our technique effectively utilizes the deductive search framework to reduce the learning problem of the neural component to a simple supervised learning setup. Further, this allows us to both train on sparingly available real-world data and still leverage powerful recurrent neural network encoders. We demonstrate the effectiveness of our method by evaluating on real-world customer scenarios by synthesizing accurate programs with up to 12 speedup compared to state-ofthe-art systems. Automatic synthesis of programs that satisfy a given specification is a classical problem in AI (Waldinger & Lee, 1969), with extensive literature in both machine learning and programming languages communities. Recently, this area has gathered widespread interest, mainly spurred by the emergence of a sub-area - Programming by Examples (PBE) (Gulwani, 2011). A PBE system synthesizes programs that map a given set of example inputs to their specified example outputs. Such systems make many tasks accessible to a wider audience as example-based specifications can be easily provided even by end users without programming skills.


Online Adaptive Methods, Universality and Acceleration

arXiv.org Machine Learning

We present a novel method for convex unconstrained optimization that, without any modifications, ensures: (i) accelerated convergence rate for smooth objectives, (ii) standard convergence rate in the general (non-smooth) setting, and (iii) standard convergence rate in the stochastic optimization setting. To the best of our knowledge, this is the first method that simultaneously applies to all of the above settings. At the heart of our method is an adaptive learning rate rule that employs importance weights, in the spirit of adaptive online learning algorithms (Duchi et al., 2011; Levy, 2017), combined with an update that linearly couples two sequences, in the spirit of (Allen-Zhu and Orecchia, 2017). An empirical examination of our method demonstrates its applicability to the above mentioned scenarios and corroborates our theoretical findings.


Modelling User's Theory of AI's Mind in Interactive Intelligent Systems

arXiv.org Machine Learning

Many interactive intelligent systems, such as recommendation and information retrieval systems, treat users as a passive data source. Yet, users form mental models of systems and instead of passively providing feedback to the queries of the system, they will strategically plan their actions within the constraints of the mental model to steer the system and achieve their goals faster. We propose to explicitly account for the user's theory of the AI's mind in the user model: the intelligent system has a model of the user having a model of the intelligent system. We study a case where the system is a contextual bandit and the user model is a Markov decision process that plans based on a simpler model of the bandit. Inference in the model can be reduced to probabilistic inverse reinforcement learning, with the nested bandit model defining the transition dynamics, and is implemented using probabilistic programming. Our results show that improved performance is achieved if users can form accurate mental models that the system can capture, implying predictability of the interactive intelligent system is important not only for the user experience but also for the design of the system's statistical models.


Difficulty-controllable Question Generation for Reading Comprehension

arXiv.org Artificial Intelligence

We investigate the difficulty levels of questions, and propose a new setting called Difficulty-controllable Question Generation (DQG). Taking as input a reading comprehension paragraph and some text fragments (i.e. answers) in the paragraph that we want to ask questions about, a DQG method needs to generate questions each of which has a given text fragment as its answer, and meanwhile the generation is under the control of specified difficulty labels---the output questions should satisfy the specified difficulty as much as possible. To solve this task, we propose an end-to-end framework to generate questions of designated difficulty levels. Specifically, we explore a few intuitions: (i) In the input sentences, the nearer a word is to the answer fragment, the more likely it is used in the question; (ii) The easier a question is, the nearer its words are to the answer fragment in the sentence; (iii) Performing difficulty control could be regarded as a problem of sentence generation towards a specified attribute or style, namely difficulty level. For evaluation, we prepared the first dataset of reading comprehension questions with difficulty labels. The results show that our framework not only generates questions of better quality under the metrics like BLEU, but also has the capability to generate questions complying with the specified difficulty labels.