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Interactive Open-Ended Learning for 3D Object Recognition

arXiv.org Artificial Intelligence

The thesis contributes in several important ways to the research area of 3D object category learning and recognition. To cope with the mentioned limitations, we look at human cognition, in particular at the fact that human beings learn to recognize object categories ceaselessly over time. This ability to refine knowledge from the set of accumulated experiences facilitates the adaptation to new environments. Inspired by this capability, we seek to create a cognitive object perception and perceptual learning architecture that can learn 3D object categories in an open-ended fashion. In this context, ``open-ended'' implies that the set of categories to be learned is not known in advance, and the training instances are extracted from actual experiences of a robot, and thus become gradually available, rather than being available since the beginning of the learning process. In particular, this architecture provides perception capabilities that will allow robots to incrementally learn object categories from the set of accumulated experiences and reason about how to perform complex tasks. This framework integrates detection, tracking, teaching, learning, and recognition of objects. An extensive set of systematic experiments, in multiple experimental settings, was carried out to thoroughly evaluate the described learning approaches. Experimental results show that the proposed system is able to interact with human users, learn new object categories over time, as well as perform complex tasks. The contributions presented in this thesis have been fully implemented and evaluated on different standard object and scene datasets and empirically evaluated on different robotic platforms.


A Framework for Explainable Text Classification in Legal Document Review

arXiv.org Artificial Intelligence

Companies regularly spend millions of dollars producing electronically-stored documents in legal matters. Recently, parties on both sides of the 'legal aisle' are accepting the use of machine learning techniques like text classification to cull massive volumes of data and to identify responsive documents for use in these matters. While text classification is regularly used to reduce the discovery costs in legal matters, it also faces a peculiar perception challenge: amongst lawyers, this technology is sometimes looked upon as a "black box", little information provided for attorneys to understand why documents are classified as responsive. In recent years, a group of AI and ML researchers have been actively researching Explainable AI, in which actions or decisions are human understandable. In legal document review scenarios, a document can be identified as responsive, if one or more of its text snippets are deemed responsive. In these scenarios, if text classification can be used to locate these snippets, then attorneys could easily evaluate the model's classification decision. When deployed with defined and explainable results, text classification can drastically enhance overall quality and speed of the review process by reducing the review time. Moreover, explainable predictive coding provides lawyers with greater confidence in the results of that supervised learning task. This paper describes a framework for explainable text classification as a valuable tool in legal services: for enhancing the quality and efficiency of legal document review and for assisting in locating responsive snippets within responsive documents. This framework has been implemented in our legal analytics product, which has been used in hundreds of legal matters. We also report our experimental results using the data from an actual legal matter that used this type of document review.


On-policy Reinforcement Learning with Entropy Regularization

arXiv.org Artificial Intelligence

Entropy regularization is an imported idea in reinforcement learning, with great success in recent algorithms like Soft Actor Critic and Soft Q Network. In this work we extend this idea into the on-policy realm. With the soft gradient policy theorem, we construct the maximum entropy reinforcement learning framework for on-policy RL. For policy gradient based on-policy algorithms, policy network is often represented as Gaussian distribution with the action variance restricted to be global for all the states observed from the environment. We propose an idea called action variance scale for policy network and find it can work collaboratively with the idea of entropy regularization. In this paper, we choose the state-of-the-art on-policy algorithm, Proximal Policy Optimization, as our basal algorithm and present Soft Proximal Policy Optimization (SPPO). PPO is a popular on-policy RL algorithm with great stability and parallelism. But like many on-policy algorithm, PPO can also suffer from low sample efficiency and local optimum problem. In the entropy-regularized framework, SPPO can guide the agent to succeed at the task while maintaining exploration by acting as randomly as possible. Our method outperforms prior works on a range of continuous control benchmark tasks, Furthermore, our method can be easily extended to large scale experiment and achieve stable learning at high throughput.


FIBS: A Generic Framework for Classifying Interval-based Temporal Sequences

arXiv.org Artificial Intelligence

We study the problem of classification of interval-based temporal sequences (IBTSs). Since common classification algorithms cannot be directly applied to IBTSs, the main challenge is to define a set of features that effectively represents the data such that learning classifiers are able to perform. Most prior work utilizes frequent pattern mining to define a feature set based on discovered patterns. However, frequent pattern mining is computationally expensive and often discovers many irrelevant patterns. To address this shortcoming, we propose the FIBS framework for classifying IBTSs. FIBS extracts features relevant to classification from IBTSs based on relative frequency and temporal relations. To avoid selecting irrelevant features, a filter-based selection strategy is incorporated into FIBS. Our empirical evaluation on five real-world datasets demonstrate the effectiveness of our methods in practice. The results provide evidence that FIBS framework effectively represents IBTSs for classification algorithms and it can even achieve better performance when the selection strategy is applied.


PySS3: A Python package implementing a novel text classifier with visualization tools for Explainable AI

arXiv.org Artificial Intelligence

A recently introduced text classifier, called SS3, has obtained state-of-the-art performance on the CLEF's eRisk tasks. SS3 was created to deal with risk detection over text streams and therefore not only supports incremental training and classification but also can visually explain its rationale. However, little attention has been paid to the potential use of SS3 as a general classifier. We believe this could be due to the unavailability of an open-source implementation of SS3. In this work, we introduce PySS3, a package that not only implements SS3 but also comes with visualization tools that allow researchers deploying robust, explainable and trusty machine learning models for text classification.


Deep Reinforcement Learning for Motion Planning of Mobile Robots

arXiv.org Artificial Intelligence

This paper presents a novel motion and trajectory planning algorithm for nonholonomic mobile robots that uses recent advances in deep reinforcement learning. Starting from a random initial state, i.e., position, velocity and orientation, the robot reaches an arbitrary target state while taking both kinematic and dynamic constraints into account. Our deep reinforcement learning agent not only processes a continuous state space it also executes continuous actions, i.e., the acceleration of wheels and the adaptation of the steering angle. We evaluate our motion and trajectory planning on a mobile robot with a differential drive in a simulation environment.


Measuring the Quality of Explanations: The System Causability Scale (SCS). Comparing Human and Machine Explanations

arXiv.org Artificial Intelligence

Recent success in Artificial Intelligence (AI) and Machine Learning (ML) allow problem solving automatically without any human intervention. Autonomous approaches can be very convenient. However, in certain domains, e.g., in the medical domain, it is necessary to enable a domain expert to understand, why an algorithm came up with a certain result. Consequently, the field of Explainable AI (xAI) rapidly gained interest worldwide in various domains, particularly in medicine. Explainable AI studies transparency and traceability of opaque AI/ML and there are already a huge variety of methods. For example with layer-wise relevance propagation relevant parts of inputs to, and representations in, a neural network which caused a result, can be highlighted. This is a first important step to ensure that end users, e.g., medical professionals, assume responsibility for decision making with AI/ML and of interest to professionals and regulators. Interactive ML adds the component of human expertise to AI/ML processes by enabling them to re-enact and retrace AI/ML results, e.g. let them check it for plausibility. This requires new human-AI interfaces for explainable AI. In order to build effective and efficient interactive human-AI interfaces we have to deal with the question of how to evaluate the quality of explanations given by an explainable AI system. In this paper we introduce our System Causability Scale (SCS) to measure the quality of explanations. It is based on our notion of Causability (Holzinger et al., 2019) combined with concepts adapted from a widely accepted usability scale.


Exclusive: Nvidia to win unconditional EU okay for $6.8 billion Mellanox buy - sources - Reuters

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BRUSSELS (Reuters) - U.S. chipmaker Nvidia (NVDA.O) is set to win unconditional EU antitrust approval for its $6.8 billion acquisition of Mellanox Technologies (MLNX.O), people familiar with the matter said on Wednesday. Nvidia, known for its powerful gaming graphics chips, is looking to boost its data center and artificial intelligence business via the takeover, its biggest deal, helping it to better compete with rival Intel (INTC.O). The European Commission, which is scheduled to decide on the deal by Dec. 19, declined to comment. Nvidia and Mellanox also declined to comment. U.S. authorities have already cleared the deal without conditions while approval is still pending in China where Mellanox has major customers such as Alibaba (BABA.N) and Baidu (BIDU.O) .


Artificial Intelligence's Foothold Increases Going Into 2020

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Artificial intelligence (AI) continues to expand its footprint in the enterprise and the economy. That's the word from the AI Index, an annual data update from Stanford University's Human-Centered Artificial Intelligence Institute. The index tracks AI growth across a range of metrics, from papers published to patents granted to employment numbers. In terms of total employment, while AI-related jobs are but a small fraction, the share is rapidly expanding. In the U.S., the share of jobs in AI-related topics increased from 0.26% of total jobs posted in 2010 to 1.32% in October 2019 -- or five-fold growth.


Internet of Medical Things Comes of Age

#artificialintelligence

What is the internet of medical things, or "IoMT" as it's sometimes called today? With the explosion of IoT use cases across industries, the medical space is no exception. Given the transformation of US healthcare to evidence-based outcomes with incentives that are beginning to align, metrics and patient feedback have become essential for care providers. Payers are increasingly interested in optimizing costs with treatments that are more effective than others. My personal experience with orthopedic sensors and the analytics possible with these sensors make me feel confident of a couple of things.