Industry
A Trust Model for Supply Chain Management
Haghpanah, Yasaman (University of Maryland, Baltimore County) | desJardins, Marie (University of Maryland, Baltimore County)
Many real-world applications, such as Supply Chain Management (SCM), can be modeled using multi-agent systems. One shortcoming of current SCM models is that their trust models are ad hoc and do not have a strong theoretical basis. We propose a trust model for SCM that is grounded in probabilistic game theory. In this model, trust can be gained through direct interactions, and/or by asking for information from other trustworthy agents. We will use this model to simulate and study supply chain market behavior.
Combining Human Reasoning and Machine Computation: Towards a Memetic Network Solution to Satisfiability
Farenzena, Daniel S. (The Federal University of Rio Grande do Sul) | Lamb, Luis C. (The Federal University of Rio Grande do Sul) | Araújo, Ricardo M. (Federal University of Pelotas)
We propose a framework where humans and computers can collaborate seamlessly to solve problems. We do so by developing and applying a network model, namely Memenets, where human knowledge and reasoning are combined with machine computation to achieve problem-solving. The development of a Memenet is done in three steps: first, we simulate a machine-only network, as previous results have shown that memenets are efficient problem-solvers. Then, we perform an experiment with human agents organized in a online network. This allows us to investigate human behavior while solving problems in a social network and to postulate principles of agent communication in Memenets. These postulates describe an initial theory of how human-computer interaction functions inside social networks. In the third stage, postulates of step two allow one to combine human and machine computation to propose an integrated Memenet-based problem-solving computing model.
Finding Semantic Inconsistencies in UMLS using Answer Set Programming
Erdogan, Halit (Sabanci University) | Bodenreider, Olivier (National Library of Medicine) | Erdem, Esra (Sabanci University)
The UMLS Metathesaurus was assembled by integrating its ancestors. We introduced an inconsistency definition for some 150 source vocabularies; it contains more than Metathesaurus concepts based on their hierarchical relations 2 million concepts (i.e., clusters of synonymous terms coming and compute all such inconsistent concepts. After that we from multiple source vocabularies identified by a Concept manually review some of the inconsistent concepts to determine Unique Identifier). The UMLS Metathesaurus contains the ones that have erroneous synonymy relations such also more than 36 million relations between these concepts, as wrong synonymy.
Progress on Agent Coordination with Cooperative Auctions
Koenig, Sven (University of Southern California) | Keskinocak, Pinar (Georgia Institute of Technology) | Tovey, Craig (Georgia Institute of Technology)
Auctions are promising decentralized methods for teams of agents to allocate and re-allocate tasks among themselves in dynamic, partially known and time-constrained domains with positive or negative synergies among tasks. Auction-based coordination systems are easy to understand, simple to implement and broadly applicable. They promise to be efficient both in communication (since agents communicate only essential summary information) and in computation (since agents compute their bids in parallel). Artificial intelligence research has explored auction-based coordination systems since the early work on contract networks, mostly from an experimental perspective. This overview paper describes our recent progress towards creating a framework for the design and analysis of cooperative auctions for agent coordination.
Comparing Position Auctions Computationally
Thompson, David Robert Martin (University of British Columbia) | Leyton-Brown, Kevin (University of British Columbia)
Modern techniques for representing games and computing their Nash equilibria are approaching the point where they can be used to analyze market games. We demonstrate this by showing how the equilibria of different position auction mechanisms can be tractably identified using these techniques. These results enable detailed and quantitative comparisons of the different auction mechanisms — in terms of both efficiency and revenue — under different preference models and equilibrium selection criteria.
Constraint Programming for Data Mining and Machine Learning
Raedt, Luc De (K. U. Leuven) | Guns, Tias (K. U. Leuven) | Nijssen, Siegfried (K. U. Leuven)
Machine learning and data mining have become aware that using constraints when learning patterns and rules can be very useful. To this end, a large number of special purpose systems and techniques have been developed for solving such constraint-based mining and learning problems. These techniques have, so far, been developed independently of the general purpose tools and principles of constraint programming known within the field of artificial intelligence. This paper shows that off-the-shelf constraint programming techniques can be applied to various pattern mining and rule learning problems (cf. also (De Raedt, Guns, and Nijssen 2008; Nijssen, Guns, and De Raedt 2009)). This does not only lead to methodologies that are more general and flexible, but also provides new insights into the underlying mining problems that allow us to improve the state-of-the-art in data mining. Such a combination of constraint programming and data mining raises a number of interesting new questions and challenges.
Automatic Derivation of Finite-State Machines for Behavior Control
Bonet, Blai (Universidad Simon Bolivar) | Palacios, Hector (Universidad Simon Bolivar) | Geffner, Hector (Universidad Pompeu Fabra &)
Finite-state controllers represent an effective action selection mechanisms widely used in domains such as video-games and mobile robotics. In contrast to the policies obtained from MDPs and POMDPs, finite-state controllers have two advantages: they are often extremely compact, and they are general, applying to many problems and not just one. A limitation of finite-state controllers, on the other hand, is that they are written by hand. In this paper, we address this limitation, presenting a method for deriving controllers automatically from models. The models represent a class of contingent problems where actions are deterministic and some fluents are observable. The problem of deriving a controller is converted into a conformant problem that is solved using classical planners, taking advantage of a complete translation into classical planning introduced recently. The controllers derived are ‘general’ in the sense that they do not solve the original problem only, but many variations as well, including changes in the size of the problem or in the uncertainty of the initial situation and action effects. Several experiments illustrating the automatic derivation of controllers are presented.
Online Learning of Uneven Terrain for Humanoid Bipedal Walking
Yi, Seung Joon (University of Pennsylvania) | Zhang, Byoung Tak (Seoul National University) | Lee, Daniel (University of Pennsylvania)
In this work, we show how to use existing hardware on The main advantage of legged locomotion over wheeled locomotion bipedal robots to address the sensing part of the problem is that legs have the capability of climbing rougher using online machine learning techniques. By incorporating terrain than wheeled or tracked vehicles. Unfortunately, this electronic compliance and foot pressure sensors, the swing ideal is often not achieved in reality, especially for the current foot is used to provide noisy estimates of the local gradient generation of bipedal humanoid robots. Many walking of the contact point, and the computed pose of the foot from controller implementations for humanoid robots assume perfectly joint encoders and the inertial measurement unit is used to flat surfaces, and even a slight deviation in the floor rapidly learn an explicit model of the surface the robot is can lead to serious instabilities in these controllers.
Community-Guided Learning: Exploiting Mobile Sensor Users to Model Human Behavior
Peebles, Daniel (Dartmouth College) | Lu, Hong (Dartmouth College) | Lane, Nicholas D. (Dartmouth College) | Choudhury, Tanzeem (Dartmouth College) | Campbell, Andrew T. (Dartmouth College)
Modeling human behavior requires vast quantities of accurately labeled training data, but for ubiquitous people-aware applications such data is rarely attainable. Even researchers make mistakes when labeling data, and consistent, reliable labels from low-commitment users are rare. In particular, users may give identical labels to activities with characteristically different signatures (e.g., labeling eating at home or at a restaurant as "dinner") or may give different labels to the same context (e.g., "work" vs. "office"). In this scenario, labels are unreliable but nonetheless contain valuable information for classification. To facilitate learning in such unconstrained labeling scenarios, we propose Community-Guided Learning (CGL), a framework that allows existing classifiers to learn robustly from unreliably-labeled user-submitted data. CGL exploits the underlying structure in the data and the unconstrained labels to intelligently group crowd-sourced data. We demonstrate how to use similarity measures to determine when and how to split and merge contributions from different labeled categories and present experimental results that demonstrate the effectiveness of our framework.
Biped Walk Learning Through Playback and Corrective Demonstration
Mericli, Cetin (Bogazici University and Carnegie Mellon University) | Veloso, Manuela (Carnegie Mellon University)
Developing a robust, flexible, closed-loop walking algorithm for a humanoid robot is a challenging task due to the complex dynamics of the general biped walk. Common analytical approaches to biped walk use simplified models of the physical reality. Such approaches are partially successful as they lead to failures of the robot walk in terms of unavoidable falls. Instead of further refining the analytical models, in this work we investigate the use of human corrective demonstrations, as we realize that a human can visually detect when the robot may be falling. We contribute a two-phase biped walk learning approach, which we experiment on the Aldebaran NAO humanoid robot. In the first phase, the robot walks following an analytical simplified walk algorithm, which is used as a black box, and we identify and save a walk cycle as joint motion commands. We then show how the robot can repeatedly and successfully play back the recorded motion cycle, even if in open-loop. In the second phase, we create a closed-loop walk by modifying the recorded walk cycle to respond to sensory data. The algorithm learns joint movement corrections to the open-loop walk based on the corrective feedback provided by a human, and on the sensory data, while walking autonomously. In our experimental results, we show that the learned closed-loop walking policy outperforms a hand-tuned closed-loop policy and the open-loop playback walk, in terms of the distance traveled by the robot without falling.