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Individualized Multilayer Tensor Learning with An Application in Imaging Analysis

arXiv.org Machine Learning

This work is motivated by multimodality breast cancer imaging data, which is quite challenging in that the signals of discrete tumor-associated microvesicles (TMVs) are randomly distributed with heterogeneous patterns. This imposes a significant challenge for conventional imaging regression and dimension reduction models assuming a homogeneous feature structure. We develop an innovative multilayer tensor learning method to incorporate heterogeneity to a higher-order tensor decomposition and predict disease status effectively through utilizing subject-wise imaging features and multimodality information. Specifically, we construct a multilayer decomposition which leverages an individualized imaging layer in addition to a modality-specific tensor structure. One major advantage of our approach is that we are able to efficiently capture the heterogeneous spatial features of signals that are not characterized by a population structure as well as integrating multimodality information simultaneously. To achieve scalable computing, we develop a new bi-level block improvement algorithm. In theory, we investigate both the algorithm convergence property, tensor signal recovery error bound and asymptotic consistency for prediction model estimation. We also apply the proposed method for simulated and human breast cancer imaging data. Numerical results demonstrate that the proposed method outperforms other existing competing methods.


Empirical confidence estimates for classification by deep neural networks

arXiv.org Machine Learning

How well can we estimate the probability that the classification, $C(f(x))$, predicted by a deep neural network is correct (or in the Top 5)? We consider the case of a classification neural network trained with the KL divergence which is assumed to generalize, as measured empirically by the test error and test loss. We present conditional probabilities for predictions based on the histogram of uncertainty metrics, which have a significant Bayes ratio. Previous work in this area includes Bayesian neural networks. Our metric is twice as predictive, based on the expected Bayes ratio, on ImageNet compared to our best tuned implementation of Bayesian dropout~\cite{gal2016dropout}. Our method uses just the softmax values and a stored histogram so it is essentially free to compute, compared to many times inference cost for Bayesian dropout.


Prescriptive Cluster-Dependent Support Vector Machines with an Application to Reducing Hospital Readmissions

arXiv.org Machine Learning

We augment linear Support Vector Machine (SVM) classifiers by adding three important features: (i) we introduce a regularization constraint to induce a sparse classifier; (ii) we devise a method that partitions the positive class into clusters and selects a sparse SVM classifier for each cluster; and (iii) we develop a method to optimize the values of controllable variables in order to reduce the number of data points which are predicted to have an undesirable outcome, which, in our setting, coincides with being in the positive class. The latter feature leads to personalized prescriptions/recommendations. We apply our methods to the problem of predicting and preventing hospital readmissions within 30-days from discharge for patients that underwent a general surgical procedure. To that end, we leverage a large dataset containing over 2.28 million patients who had surgeries in the period 2011--2014 in the U.S. The dataset has been collected as part of the American College of Surgeons National Surgical Quality Improvement Program (NSQIP).


Improving Safety in Reinforcement Learning Using Model-Based Architectures and Human Intervention

arXiv.org Artificial Intelligence

Recent progress in AI and Reinforcement learning has shown great success in solving complex problems with high dimensional state spaces. However, most of these successes have been primarily in simulated environments where failure is of little or no consequence. Most real-world applications, however, require training solutions that are safe to operate as catastrophic failures are inadmissible especially when there is human interaction involved. Currently, Safe RL systems use human oversight during training and exploration in order to make sure the RL agent does not go into a catastrophic state. These methods require a large amount of human labor and it is very difficult to scale up. We present a hybrid method for reducing the human intervention time by combining model-based approaches and training a supervised learner to improve sample efficiency while also ensuring safety. We evaluate these methods on various grid-world environments using both standard and visual representations and show that our approach achieves better performance in terms of sample efficiency, number of catastrophic states reached as well as overall task performance compared to traditional model-free approaches


'Space drones' being used to explore lava tubes in Iceland could help NASA detect life on Mars

Daily Mail - Science & tech

Technology used to map the interior of Icelandic lava tubes could be used to explore deep caves on Mars and the moon, scientists say. 'Space drones', or LiDAR-equipped drones, which stands for Light Detection and Ranging, are currently used to examine the lava tube's shape and its ice formations. The team, from the SETI Institute and Astrobotic Technology, was investigating the Lofthellir Lava Tube Ice Cave in the remote Myvatn region of Iceland. Scientists are hoping to use the same technology used to map the interior of Icelandic lava tubes to explore deep caves on Mars. SETI's mission is to explore and examine the origin and nature of life in the universe.


Artificial Intelligence : from Research to Application ; the Upper-Rhine Artificial Intelligence Symposium (UR-AI 2019)

arXiv.org Artificial Intelligence

The TriRhenaTech alliance universities and their partners presented their competences in the field of artificial intelligence and their cross-border cooperations with the industry at the tri-national conference 'Artificial Intelligence : from Research to Application' on March 13th, 2019 in Offenburg. The TriRhenaTech alliance is a network of universities in the Upper Rhine Trinational Metropolitan Region comprising of the German universities of applied sciences in Furtwangen, Kaiserslautern, Karlsruhe, and Offenburg, the Baden-Wuerttemberg Cooperative State University Loerrach, the French university network Alsace Tech (comprised of 14 'grandes \'ecoles' in the fields of engineering, architecture and management) and the University of Applied Sciences and Arts Northwestern Switzerland. The alliance's common goal is to reinforce the transfer of knowledge, research, and technology, as well as the cross-border mobility of students.


Modeling Intelligent Decision Making Command And Control Agents: An Application to Air Defense

arXiv.org Artificial Intelligence

The paper is a half-way between the agent technology and the mathematical reasoning to model tactical decision making tasks. These models are applied to air defense (AD) domain for command and control (C2). It also addresses the issues related to evaluation of agents. The agents are designed and implemented using the agent-programming paradigm. The agents are deployed in an air combat simulated environment for performing the tasks of C2 like electronic counter counter measures, threat assessment, and weapon allocation. The simulated AD system runs without any human intervention, and represents state-of-the-art model for C2 autonomy. The use of agents as autonomous decision making entities is particularly useful in view of futuristic network centric warfare.


Towards Standardization of Data Licenses: The Montreal Data License

arXiv.org Machine Learning

This paper provides a taxonomy for the licensing of data in the fields of artificial intelligence and machine learning. The paper's goal is to build towards a common framework for data licensing akin to the licensing of open source software. Increased transparency and resolving conceptual ambiguities in existing licensing language are two noted benefits of the approach proposed in the paper. In parallel, such benefits may help foster fairer and more efficient markets for data through bringing about clearer tools and concepts that better define how data can be used in the fields of AI and ML. The paper's approach is summarized in a new family of data license language - \textit{the Montreal Data License (MDL)}. Alongside this new license, the authors and their collaborators have developed a web-based tool to generate license language espousing the taxonomies articulated in this paper.


Germany Risks U.S. Backlash If It Hires Chinese Company Huawei For 5G Tech

NPR Technology

Tomorrow, Germany begins auctioning frequencies to build 5G mobile networks. It is both a highly technical event and the center of a geopolitical storm. Like much of Europe, Germany is squeezed between its economic ties to China and its longtime alliance with the U.S. NPR's Joanna Kakissis reports from Berlin. COMPUTER-GENERATED VOICE: To keep your estimated arrival time... JOANNA KAKISSIS, BYLINE: 5G will not just allow you to download movies in seconds on your smartphone. Since it's supposed to be up to 1,000 times faster than current mobile speeds, it can handle communication for self-driving cars, for example.


1 Year After Uber's Fatal Crash, Robocars Carry On Quietly

WIRED

In America, 2018 was supposed to be a very big year for self-driving cars. Uber quietly prepped to launch a robo-taxi service. Waymo said riders would be able to catch a driverless ride by year's end. General Motors' Cruise said it would start testing in New York City, the country's traffic chaos capital. Congress was poised to pass legislation that would set broad outlines for federal regulation of the tech.