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A Practical Automata-Based Technique for Reasoning in Expressive Description Logics
Calvanese, Diego (Free University of Bozen-Bolzano) | Carbotta, Domenico (Vienna University of Technology) | Ortiz, Magdalena (Vienna University of Technology)
The automata-based approach is based on translating a knowledge base (KB) whose satisfiability is to be checked In this work we describe the theoretical foundations into some variant of automata on infinite trees that accepts and the implementation of a new automata-based tree-shaped models of the KB, and checking such an automaton technique for reasoning over expressive Description for non-emptiness. This approach is powerful and flexible. Logics that is worst-case optimal and lends itself It is acknowledged that it provides a very robust basis to an efficient implementation. In order to show for showing worst-case optimal complexity upper bounds, the feasibility of the approach, we have realized a and has been applied for a wide range of expressive DLs working prototype of a reasoner based upon these and reasoning services (cf.
User Similarity from Linked Taxonomies: Subjective Assessments of Items
Nakatsuji, Makoto (NTT Cyber Solutions Laboratories) | Fujiwara, Yasuhiro (NTT Cyber Space Laboratories) | Uchiyama, Toshio (NTT Cyber Solutions Laboratories) | Fujimura, Ko (NTT Cyber Solutions Laboratories)
Subjective assessments (SAs) are assigned by users against items, such as โelegantโ and โgorgeousโ, and are common in reviews/tags in many online-sites. However, previous studies fail to effectively use SAs for improving recommendations because few users rate the same items with the same SAs, which triggers the sparsity problem in collaborative filtering. We propose a novel algorithm that links a taxonomy of items to a taxonomy of SAs to assess user interests in detail. That is, it merges the SAs assigned by users against an item into subjective classes (SCs) and reflects the SAs/SCs assigned to an item to its classes. Thus, it can measure the similarity of users from not only SAs/SCs assigned to items but also their classes, which overcomes the sparsity problem. Our evaluation, which uses data from a popular restaurant review site, shows that our method generates more accurate recommendations than previous methods. Furthermore, we find that SAs frequently assigned on a few item classes are more useful than those widely assigned against many item classes in terms of recommendation accuracy.
Making Better Informed Trust Decisions with Generalized Fact-Finding
Pasternack, Jeff (University of Illinois, Urbana-Champaign) | Roth, Dan (University of Illinois, Urbana-Champaign)
Information retrieval may suggest a document, and information extraction may tell us what it says, but which information sources do we trust and which assertions do we believe when different authors make conflicting claims? Trust algorithms known as fact-finders attempt to answer these questions, but consider only which source makes which claim, ignoring a wealth of background knowledge and contextual detail such as the uncertainty in the information extraction of claims from documents, attributes of the sources, the degree of similarity among claims, and the degree of certainty expressed by the sources. We introduce a new, generalized fact-finding framework able to incorporate this additional information into the fact-finding process. Experiments using several state-of-the-art fact-finding algorithms demonstrate that generalized fact-finders achieve significantly better performance than their original variants on both semi-synthetic and real-world problems.
Multi-Kernel Multi-Label Learning with Max-Margin Concept Network
Zhang, Wei (Fudan University) | Xue, Xiangyang (Fudan University) | Fan, Jianping (University of North Carolina, Charlotte) | Huang, Xiaojing (Fudan University) | Wu, Bin (Fudan University) | Liu, Mingjie (Fudan University)
In this paper, a novel method is developed for enabling Multi-Kernel Multi-Label Learning. Inter-label dependency and similarity diversity are simultaneously leveraged in the proposed method. A concept network is constructed to capture the inter-label correlations for classifier training. Maximal margin approach is used to effectively formulate the feature-label associations and the label-label correlations. Specific kernels are learned not only for each label but also for each pair of the inter-related labels. By learning the eigenfunctions of the kernels, the similarity between a new data point and the training samples can be computed in the online mode. Our experimental results on real datasets (web pages, images, music, and bioinformatics) have demonstrated the effectiveness of our method.
Behaviour Recognition in Smart Homes
Chua, Sook-Ling (Massey University) | Marsland, Stephen (Massey University) | Guesgen, Hans W. (Massey University)
Behaviour recognition aims to infer the particular behaviours of the inhabitant in a smart home from a series of sensor readings from around the house. There are many reasons to recognise human behaviours; one being to monitor the elderly or cognitively impaired and detect potentially dangerous behaviours. We view the behaviour recognition problem as the task of mapping the sensory outputs to a sequence of recognised activities. This research focuses on the development of machine learning methods to find an approximation to the mapping between sensor outputs and behaviours. However, learning the mapping raises an important issue, which is that the training data is not necessarily annotated with exemplar behaviours of the inhabitant. This doctoral study takes several steps towards addressing the problem of finding an approximation to this mapping, beginning with separate investigations on current methods proposed in the literature, identifying useful sensory outputs for behaviour recognition, and concluding by proposing two directions: one using supervised learning on annotated sensory stream and one using unsupervised learning on unannotated ones.
Line Orthogonality in Adjacency Eigenspace with Application to Community Partition
Wu, Leting (University of North Carolina at Charlotte) | Ying, Xiaowei (University of North Carolina at Charlotte) | Wu, Xintao (University of North Carolina at Charlotte) | Zhou, Zhi-Hua (Nanjing University)
Different from Laplacian or normal matrix, the properties of the adjacency eigenspace received much less attention. Recent work showed that nodes projected into the adjacency eigenspace exhibit an orthogonal line pattern and nodes from the same community locate along the same line. In this paper, we conduct theoretical studies based on graph perturbation to demonstrate why this line orthogonality property holds in the adjacency eigenspace and why it generally disappears in the Laplacian and normal eigenspaces. Using the orthogonality property in the adjacency eigenspace, we present a graph partition algorithm, AdjCluster, which first projects node coordinates to the unit sphere and then applies the classic k-means to find clusters. Empirical evaluations on synthetic data and real-world social networks validate our theoretical findings and show the effectiveness of our graph partition algorithm.
Multiagent Hierarchical Learning from Demonstration
Sullivan, Keith (George Mason University)
Programming agent behaviors is a tedious task. In HITAB, agents learn a hierarchical finite state automata The difficulty increases in a multiagent setting due to the increased (HFA) represented as a Moore machine where individual size of the design space. Density of interactions, the states correspond to agent behaviors or another HFA. An number of agents and the agent's heterogeneity (both capabilities HFA is built iteratively: staring with a behavior library consisting and behaviors) all contribute to the larger design space. The now expanded One training approach is Learning from Demonstration behavior library is then used to train an even more (LfD) in which agents learn behaviors in real-time based on complex behavior which is then saved to the library, and provided examples from a human demonstrator.
Strategy Learning for Autonomous Agents in Smart Grid Markets
Reddy, Prashant P. (Carnegie Mellon University) | Veloso, Manuela M. (Carnegie Mellon University)
Distributed electricity producers, such as small wind farms and solar installations, pose several technical and economic challenges in Smart Grid design. One approach to addressing these challenges is through Broker Agents who buy electricity from distributed producers, and also sell electricity to consumers, via a Tariff Market--a new market mechanism where Broker Agents publish concurrent bid and ask prices. We investigate the learning of pricing strategies for an autonomous Broker Agent to profitably participate in a Tariff Market. We employ Markov Decision Processes (MDPs) and reinforcement learning. An important concern with this method is that even simple representations of the problem domain result in very large numbers of states in the MDP formulation because market prices can take nearly arbitrary real values. In this paper, we present the use of derived state space features, computed using statistics on Tariff Market prices and Broker Agent customer portfolios, to obtain a scalable state representation. We also contribute a set of pricing tactics that form building blocks in the learned Broker Agent strategy. We further present a Tariff Market simulation model based on real-world data and anticipated market dynamics. We use this model to obtain experimental results that show the learned strategy performing vastly better than a random strategy and significantly better than two other non-learning strategies.
Artificial Intelligence and Human Thinking
Kowalski, Robert Anthony (Imperial College London)
Research in AI has built upon the tools and techniques of many different disciplines, including formal logic, probability theory, decision theory, management science, linguistics and philosophy. However, the application of these disciplines in AI has necessitated the development of many enhancements and extensions. Among the most powerful of these are the methods of computational logic. I will argue that computational logic, embedded in an agent cycle, combines and improves upon both traditional logic and classical decision theory. I will also argue that many of its methods can be used, not only in AI, but also in ordinary life, to help people improve their own human intelligence without the assistance of computers.
Enhancing Case Adaptation with Introspective Reasoning and Web Mining
Leake, David (Indiana University) | Powell, Jay (Indiana University)
Case-based problem-solving systems reason by retrieving relevant prior cases and adapting their solutions to fit new circumstances. The ability of case-based reasoning (CBR) to reason from ungeneralized episodes can benefit knowledge acquisition, but acquiring the needed case adaptation knowledge has proven challenging. This paper presents a method for alleviating this problem with just-in-time gathering of case adaptation knowledge, based on introspective reasoning and mining of Web knowledge sources. The approach combines knowledge planning with introspective reasoning to guide recovery from case adaptation failures and reinforcement learning to guide selection of knowledge sources. The failure recovery and knowledge source selection methods have been tested in three highly different domains with encouraging results. The paper closes with a discussion of limitations and future steps.