Government
NASA's Insight Mission: When will it land and why should we care?
NASA's six-month expedition to reach Mars to study its interior will take seven minutes to land on Monday at 20:00 GMT. InSight Lander - the Interior Exploration using Seismic Investigations, Geodesy and Heat Transport - is the US space agency's first craft dedicated to peer beneath Mars' surface and monitor its interior. According to NASA, it is the first outer space robotic explorer designed to give the billions-years-old Mars a "thorough checkup" by studying its crust, mantle and core. Out of the 44 NASA missions sent to Mars, only 18 have been successful. The "seven minutes of terror", which are possibly the riskiest in the entire mission, will be when the robotic spacecraft will enter the Martian atmopshere at supersonic speed, then touchdown on the red planet's region called Elysium Planitia.
Learning Robust Representations for Automatic Target Recognition
Goodwin, Justin A., Brown, Olivia M., Killian, Taylor W., Son, Sung-Hyun
Radio frequency (RF) sensors are used alongside other sensing modalities to provide rich representations of the world. Given the high variability of complex-valued target responses, RF systems are susceptible to attacks masking true target characteristics from accurate identification. In this work, we evaluate different techniques for building robust classification architectures exploiting learned physical structure in received synthetic aperture radar signals of simulated 3D targets.
HOGWILD!-Gibbs can be PanAccurate
Daskalakis, Constantinos, Dikkala, Nishanth, Jayanti, Siddhartha
Asynchronous Gibbs sampling has been recently shown to be fast-mixing and an accurate method for estimating probabilities of events on a small number of variables of a graphical model satisfying Dobrushin's condition~\cite{DeSaOR16}. We investigate whether it can be used to accurately estimate expectations of functions of {\em all the variables} of the model. Under the same condition, we show that the synchronous (sequential) and asynchronous Gibbs samplers can be coupled so that the expected Hamming distance between their (multivariate) samples remains bounded by $O(\tau \log n),$ where $n$ is the number of variables in the graphical model, and $\tau$ is a measure of the asynchronicity. A similar bound holds for any constant power of the Hamming distance. Hence, the expectation of any function that is Lipschitz with respect to a power of the Hamming distance, can be estimated with a bias that grows logarithmically in $n$. Going beyond Lipschitz functions, we consider the bias arising from asynchronicity in estimating the expectation of polynomial functions of all variables in the model. Using recent concentration of measure results, we show that the bias introduced by the asynchronicity is of smaller order than the standard deviation of the function value already present in the true model. We perform experiments on a multi-processor machine to empirically illustrate our theoretical findings.
EnResNet: ResNet Ensemble via the Feynman-Kac Formalism
Wang, Bao, Yuan, Binjie, Shi, Zuoqiang, Osher, Stanley J.
We propose a simple yet powerful ResNet ensemble algorithm which consists of two components: First, we modify the base ResNet by adding variance specified Gaussian noise to the output of each original residual mapping. Second, we average over the production of multiple parallel and jointly trained modified ResNets to get the final prediction. Heuristically, these two simple steps give an approximation to the well-known Feynman-Kac formula for representing the solution of a transport equation with viscosity, or a convection-diffusion equation. This simple ensemble algorithm improves neural nets' generalizability and robustness towards adversarial attack. In particular, for the CIFAR10 benchmark, with the projected gradient descent adversarial training, we show that even an ensemble of two ResNet20 leads to a 5$\%$ higher accuracy towards the strongest iterative fast gradient sign attack than the state-of-the-art adversarial defense algorithm.
Noisy Computations during Inference: Harmful or Helpful?
We study two aspects of noisy computations during inference. The first aspect is how to mitigate their side effects for naturally trained deep learning systems. One of the motivations for looking into this problem is to reduce the high power cost of conventional computing of neural networks through the use of analog neuromorphic circuits. Traditional GPU/CPU-centered deep learning architectures exhibit bottlenecks in power-restricted applications (e.g., embedded systems). The use of specialized neuromorphic circuits, where analog signals passed through memory-cell arrays are sensed to accomplish matrix-vector multiplications, promises large power savings and speed gains but brings with it the problems of limited precision of computations and unavoidable analog noise. We manage to improve inference accuracy from 21.1% to 99.5% for MNIST images, from 29.9% to 89.1% for CIFAR10, and from 15.5% to 89.6% for MNIST stroke sequences with the presence of strong noise (with signal-to-noise power ratio being 0 dB) by noise-injected training and a voting method. This observation promises neural networks that are insensitive to inference noise, which reduces the quality requirements on neuromorphic circuits and is crucial for their practical usage. The second aspect is how to utilize the noisy inference as a defensive architecture against black-box adversarial attacks. During inference, by injecting proper noise to signals in the neural networks, the robustness of adversarially-trained neural networks against black-box attacks has been further enhanced by 0.5% and 1.13% for two adversarially trained models for MNIST and CIFAR10, respectively.
DynamicGEM: A Library for Dynamic Graph Embedding Methods
Goyal, Palash, Chhetri, Sujit Rokka, Mehrabi, Ninareh, Ferrara, Emilio, Canedo, Arquimedes
DynamicGEM is an open-source Python library for learning node representations of dynamic graphs. It consists of state-of-the-art algorithms for defining embeddings of nodes whose connections evolve over time. The library also contains the evaluation framework for four downstream tasks on the network: graph reconstruction, static and temporal link prediction, node classification, and temporal visualization. We have implemented various metrics to evaluate the state-of-the-art methods, and examples of evolving networks from various domains. We have easy-to-use functions to call and evaluate the methods and have extensive usage documentation. Furthermore, DynamicGEM provides a template to add new algorithms with ease to facilitate further research on the topic.
AI Fairness for People with Disabilities: Point of View
We consider how fair treatment in society for people with disabilities might be impacted by the rise in the use of artificial intelligence, and especially machine learning methods. We argue that fairness for people with disabilities is different to fairness for other protected attributes such as age, gender or race. One major difference is the extreme diversity of ways disabilities manifest, and people adapt. Secondly, disability information is highly sensitive and not always shared, precisely because of the potential for discrimination. Given these differences, we explore definitions of fairness and how well they work in the disability space. Finally, we suggest ways of approaching fairness for people with disabilities in AI applications.
Abduction-Based Explanations for Machine Learning Models
Ignatiev, Alexey, Narodytska, Nina, Marques-Silva, Joao
The growing range of applications of Machine Learning (ML) in a multitude of settings motivates the ability of computing small explanations for predictions made. Small explanations are generally accepted as easier for human decision makers to understand. Most earlier work on computing explanations is based on heuristic approaches, providing no guarantees of quality, in terms of how close such solutions are from cardinality- or subset-minimal explanations. This paper develops a constraint-agnostic solution for computing explanations for any ML model. The proposed solution exploits abductive reasoning, and imposes the requirement that the ML model can be represented as sets of constraints using some target constraint reasoning system for which the decision problem can be answered with some oracle. The experimental results, obtained on well-known datasets, validate the scalability of the proposed approach as well as the quality of the computed solutions.
AI & Global Governance: Three Paths Towards a Global Governance of Artificial Intelligence - Centre for Policy Research at United Nations University
Inc. shut down a project it had been developing for four years, a recruitment tool driven by machine learning. The concept was a simple and appealing one: at its core, the project aimed to develop an algorithm that would sort incoming job applications to isolate the short list for managers to use in making their final selections. Anyone who has been involved in such a process knows that isolating the top five or ten resumés from dozens of applicants is a time-consuming job. Any process that brings logic and speed to this stage of the recruitment chain can only be a good thing. But algorithms are only as good as the data used to drive them, and in the Amazon case the machine "learning" was based on patterns in applications submitted to the firm in the previous ten years.
Scientists Built an AI Inspired by HAL 9000 And What Could Go Wrong, Really
NASA's newest plan is to launch crewed missions to Mars in the 2030s, and we'll need the most advanced and reliable space technology to help get us there safe and sound. That's where HAL 9000 – the villainous, insane killbot from 2001: A Space Odyssey – comes in. Believe it or not, sci-fi's most notorious murder machine was the inspirational basis for a new HAL-like cognitive computer system designed to autonomously run planetary space stations for real one day. If you're thinking oh god no please god no don't worry. AI and robotics developer Pete Bonasso from Houston-based TRACLabs says his new CASE prototype ("cognitive architecture for space agents") mimics HAL purely in a technological sense – ie.