Stanford University
Viewpoint: Artificial Intelligence Accidents Waiting to Happen?
Bianchi, Federico (Stanford University) | Cercas Curry, Amanda (Bocconi University) | Hovy, Dirk (Bocconi University)
Artificial Intelligence (AI) is at a crucial point in its development: stable enough to be used in production systems, and increasingly pervasive in our lives. What does that mean for its safety? In his book Normal Accidents, the sociologist Charles Perrow proposed a framework to analyze new technologies and the risks they entail. He showed that major accidents are nearly unavoidable in complex systems with tightly coupled components if they are run long enough. In this essay, we apply and extend Perrow’s framework to AI to assess its potential risks. Today’s AI systems are already highly complex, and their complexity is steadily increasing. As they become more ubiquitous, different algorithms will interact directly, leading to tightly coupled systems whose capacity to cause harm we will be unable to predict. We argue that under the current paradigm, Perrow’s normal accidents apply to AI systems and it is only a matter of time before one occurs. This article appears in the AI & Society track.
TOOLTANGO: Common sense Generalization in Predicting Sequential Tool Interactions for Robot Plan Synthesis
Tuli, Shreshth | Bansal, Rajas (Stanford University) | Paul, Rohan (Indian Institute of Technology Delhi) | null, Mausam (Indian Institute of Technology Delhi)
Robots assisting us in environments such as factories or homes must learn to make use of objects as tools to perform tasks, for instance, using a tray to carry objects. We consider the problem of learning common sense knowledge of when a tool may be useful and how its use may be composed with other tools to accomplish a high-level task instructed by a human. Specifically, we introduce a novel neural model, termed TOOLTANGO, that first predicts the next tool to be used, and then uses this information to predict the next action. We show that this joint model can inform learning of a fine-grained policy enabling the robot to use a particular tool in sequence and adds a significant value in making the model more accurate. TOOLTANGO encodes the world state, comprising objects and symbolic relationships between them, using a graph neural network and is trained using demonstrations from human teachers instructing a virtual robot in a physics simulator. The model learns to attend over the scene using knowledge of the goal and the action history, finally decoding the symbolic action to execute. Crucially, we address generalization to unseen environments where some known tools are missing, but unseen alternative tools are present. We show that by augmenting the representation of the environment with pre-trained embeddings derived from a knowledge-base, the model can generalize effectively to novel environments. Experimental results show at least 48.8-58.1% absolute improvement over the baselines in predicting successful symbolic plans for a simulated mobile manipulator in novel environments with unseen objects. This work takes a step in the direction of enabling robots to rapidly synthesize robust plans for complex tasks, particularly in novel settings.
Scalable Online Planning for Multi-Agent MDPs
Choudhury, Shushman (Lacuna) | Gupta, Jayesh K. (Microsoft) | Morales, Peter (Microsoft) | Kochenderfer, Mykel J. (Stanford University)
We present a scalable tree search planning algorithm for large multi-agent sequential decision problems that require dynamic collaboration. Teams of agents need to coordinate decisions in many domains, but naive approaches fail due to the exponential growth of the joint action space with the number of agents. We circumvent this complexity through an approach that allows us to trade computation for approximation quality and dynamically coordinate actions. Our algorithm comprises three elements: online planning with Monte Carlo Tree Search (MCTS), factored representations of local agent interactions with coordination graphs, and the iterative Max-Plus method for joint action selection. We evaluate our approach on the benchmark SysAdmin domain with static coordination graphs and achieve comparable performance with much lower computation cost than our MCTS baselines. We also introduce a multi-drone delivery domain with dynamic coordination graphs, and demonstrate how our approach scales to large problems on this domain that are intractable for other MCTS methods.
Computing Bayes-Nash Equilibria in Combinatorial Auctions with Verification
Bosshard, Vitor (University of Zurich) | Bünz, Benedikt (Stanford University) | Lubin, Benjamin (Boston University) | Seuken, Sven (University of Zurich)
We present a new algorithm for computing pure-strategy ε-Bayes-Nash equilibria (ε-BNEs) in combinatorial auctions with continuous value and action spaces. An essential innovation of our algorithm is to separate the algorithm's search phase (for finding the ε-BNE) from the verification phase (for computing the ε). Using this approach, we obtain an algorithm that is both very fast and provides theoretical guarantees on the ε it finds. Our main technical contribution is a verification method which allows us to upper bound the ε across the whole continuous value space without making assumptions about the mechanism. Using our algorithm, we can now compute ε-BNEs in multi-minded domains that are significantly more complex than what was previously possible to solve. We release our code under an open-source license to enable researchers to perform algorithmic analyses of auctions, to enable bidders to analyze different strategies, and to facilitate many other applications.
Reports of the Workshops Held at the 2018 International AAAI Conference on Web and Social Media
Editor, Managing (AAAI) | An, Jisun (Qatar Computing Research Institute) | Chunara, Rumi (New York University) | Crandall, David J. (Indiana University) | Frajberg, Darian (Politecnico di Milano) | French, Megan (Stanford University) | Jansen, Bernard J. (Qatar Computing Research Institute) | Kulshrestha, Juhi (GESIS - Leibniz Institute for the Social Sciences) | Mejova, Yelena (Qatar Computing Research Institute) | Romero, Daniel M. (University of Michigan) | Salminen, Joni (Qatar Computing Research Institute) | Sharma, Amit (Microsoft Research India) | Sheth, Amit (Wright State University) | Tan, Chenhao (University of Colorado Boulder) | Taylor, Samuel Hardman (Cornell University) | Wijeratne, Sanjaya (Wright State University)
The Workshop Program of the Association for the Advancement of Artificial Intelligence’s 12th International Conference on Web and Social Media (AAAI-18) was held at Stanford University, Stanford, California USA, on Monday, June 25, 2018. There were fourteen workshops in the program: Algorithmic Personalization and News: Risks and Opportunities; Beyond Online Data: Tackling Challenging Social Science Questions; Bridging the Gaps: Social Media, Use and Well-Being; Chatbot; Data-Driven Personas and Human-Driven Analytics: Automating Customer Insights in the Era of Social Media; Designed Data for Bridging the Lab and the Field: Tools, Methods, and Challenges in Social Media Experiments; Emoji Understanding and Applications in Social Media; Event Analytics Using Social Media Data; Exploring Ethical Trade-Offs in Social Media Research; Making Sense of Online Data for Population Research; News and Public Opinion; Social Media and Health: A Focus on Methods for Linking Online and Offline Data; Social Web for Environmental and Ecological Monitoring and The ICWSM Science Slam. Workshops were held on the first day of the conference. Workshop participants met and discussed issues with a selected focus — providing an informal setting for active exchange among researchers, developers, and users on topics of current interest. Organizers from nine of the workshops submitted reports, which are reproduced in this report. Brief summaries of the other five workshops have been reproduced from their website descriptions.
Reports on the 2018 AAAI Spring Symposium Series
Amato, Christopher (Northeastern University) | Ammar, Haitham Bou (PROWLER.io) | Churchill, Elizabeth (Google) | Karpas, Erez (Technion - Israel Institute of Technology) | Kido, Takashi (Stanford University) | Kuniavsky, Mike (Parc) | Lawless, W. F. (Paine College) | Rossi, Francesca (IBM T. J. Watson Research Center and University of Padova) | Oliehoek, Frans A. (TU Delft) | Russell, Stephen (US Army Research Laboratory) | Takadama, Keiki (University of Electro-Communications) | Srivastava, Siddharth (Arizona State University) | Tuyls, Karl (Google DeepMind) | Allen, Philip Van (Art Center College of Design) | Venable, K. Brent (Tulane University and IHMC) | Vrancx, Peter (PROWLER.io) | Zhang, Shiqi (Cleveland State University)
The Association for the Advancement of Artificial Intelligence, in cooperation with Stanford University’s Department of Computer Science, presented the 2018 Spring Symposium Series, held Monday through Wednesday, March 26–28, 2018, on the campus of Stanford University. The seven symposia held were AI and Society: Ethics, Safety and Trustworthiness in Intelligent Agents; Artificial Intelligence for the Internet of Everything; Beyond Machine Intelligence: Understanding Cognitive Bias and Humanity for Well-Being AI; Data Efficient Reinforcement Learning; The Design of the User Experience for Artificial Intelligence (the UX of AI); Integrated Representation, Reasoning, and Learning in Robotics; Learning, Inference, and Control of Multi-Agent Systems. This report, compiled from organizers of the symposia, summarizes the research of five of the symposia that took place.
Online Algorithms for POMDPs with Continuous State, Action, and Observation Spaces
Sunberg, Zachary N. (Stanford University) | Kochenderfer, Mykel J. (Stanford University)
Online solvers for partially observable Markov decision processes have been applied to problems with large discrete state spaces, but continuous state, action, and observation spaces remain a challenge. This paper begins by investigating double progressive widening (DPW) as a solution to this challenge. However, we prove that this modification alone is not sufficient because the belief representations in the search tree collapse to a single particle causing the algorithm to converge to a policy that is suboptimal regardless of the computation time. This paper proposes and evaluates two new algorithms, POMCPOW and PFT-DPW, that overcome this deficiency by using weighted particle filtering. Simulation results show that these modifications allow the algorithms to be successful where previous approaches fail.
Learning with Weak Supervision from Physics and Data-Driven Constraints
Ren, Hongyu (Peking University) | Stewart, Russell (Stanford University) | Song, Jiaming (Stanford University) | Kuleshov, Volodymyr (Stanford University) | Ermon, Stefano (Stanford University)
In many applications of machine learning, labeled data is scarce and obtaining additional labels is expensive. We introduce a new approach to supervising learning algorithms without labels by enforcing a small number of domain-specific constraints over the algorithms’ outputs. The constraints can be provided explicitly based on prior knowledge — e.g. we may require that objects detected in videos satisfy the laws of physics — or implicitly extracted from data using a novel framework inspired by adversarial training. We demonstrate the effectiveness of constraint-based learning on a variety of tasks — including tracking, object detection, and human pose estimation — and we find that algorithms supervised with constraints achieve high accuracies with only a small amount of labels, or with no labels at all in some cases.
A Panel on Cybernetics and the User Experience of AI Systems
Martelaro, Nikolas (Stanford University) | Ju, Wendy (Cornell Tech)
Cybernetics was influential in the early age of AI and might hold the keys towards making AI systems more interactive. Our panel will explore cybernetics as a useful framework for designers of artificially intelligent (AI) systems. Our four panelists---Hugh Dubberly, Deborah Forster, Jody Medich, and Paul Pangaro---will each discuss how they have used cybernetic theory in their own work. We will then delve into a discussion about the future design of AI systems and the areas where cybernetic theory may prove useful for user experience design.
Multi-Layer Multi-View Classification for Alzheimer’s Disease Diagnosis
Zhang, Changqing (University of North Carolina at Chapel Hill) | Adeli, Ehsan (Stanford University) | Zhou, Tao (University of North Carolina at Chapel Hill) | Chen, Xiaobo (University of North Carolina at Chapel Hill) | Shen, Dinggang (University of North Carolina at Chapel Hill)
In this paper, we propose a novel multi-view learning method for Alzheimer's Disease (AD) diagnosis, using neuroimaging and genetics data. Generally, there are several major challenges associated with traditional classification methods on multi-source imaging and genetics data. First, the correlation between the extracted imaging features and class labels is generally complex, which often makes the traditional linear models ineffective. Second, medical data may be collected from different sources (i.e., multiple modalities of neuroimaging data, clinical scores or genetics measurements), therefore, how to effectively exploit the complementarity among multiple views is of great importance. In this paper, we propose a Multi-Layer Multi-View Classification (ML-MVC) approach, which regards the multi-view input as the first layer, and constructs a latent representation to explore the complex correlation between the features and class labels. This captures the high-order complementarity among different views, as we exploit the underlying information with a low-rank tensor regularization. Intrinsically, our formulation elegantly explores the nonlinear correlation together with complementarity among different views, and thus improves the accuracy of classification. Finally, the minimization problem is solved by the Alternating Direction Method of Multipliers (ADMM). Experimental results on Alzheimer's Disease Neuroimaging Initiative (ADNI) data sets validate the effectiveness of our proposed method.