Asia
Reports of the AAAI 2010 Fall Symposia
Azevedo, Roger (McGill University) | Biswas, Gautam (Vanderbilt University) | Bohus, Dan (Microsoft Research) | Carmichael, Ted (University of North Carolina at Charlotte) | Finlayson, Mark (Massachusetts Institute of Technology) | Hadzikadic, Mirsad (University of North Carolina at Charlotte) | Havasi, Catherine (Massachusetts Institute of Technology) | Horvitz, Eric (Microsoft Research) | Kanda, Takayuki (ATR Intelligent Robotics and Communications Laboratories) | Koyejo, Oluwasanmi (University of Texas at Austin) | Lawless, William (Paine College) | Lenat, Doug (Cycorp) | Meneguzzi, Felipe (Carnegie Mellon University) | Mutlu, Bilge (University of Wisconsin, Madison) | Oh, Jean (Carnegie Mellon University) | Pirrone, Roberto (University of Palermo) | Raux, Antoine (Honda Research Institute USA) | Sofge, Donald (Naval Research Laboratory) | Sukthankar, Gita (University of Central Florida) | Durme, Benjamin Van (Johns Hopkins University)
The Association for the Advancement of Artificial Intelligence was pleased to present the 2010 Fall Symposium Series, held Thursday through Saturday, November 11-13, at the Westin Arlington Gateway in Arlington, Virginia. The titles of the eight symposia are as follows: (1) Cognitive and Metacognitive Educational Systems; (2) Commonsense Knowledge; (3) Complex Adaptive Systems: Resilience, Robustness, and Evolvability; (4) Computational Models of Narrative; (5) Dialog with Robots; (6) Manifold Learning and Its Applications; (7) Proactive Assistant Agents ; and (8) Quantum Informatics for Cognitive, Social, and Semantic Processes. The highlights of each symposium are presented in this report.
Metamodel-based importance sampling for the simulation of rare events
Dubourg, V., Deheeger, F., Sudret, B.
In the field of structural reliability, the Monte-Carlo estimator is considered as the reference probability estimator. However, it is still untractable for real engineering cases since it requires a high number of runs of the model. In order to reduce the number of computer experiments, many other approaches known as reliability methods have been proposed. A certain approach consists in replacing the original experiment by a surrogate which is much faster to evaluate. Nevertheless, it is often difficult (or even impossible) to quantify the error made by this substitution. In this paper an alternative approach is developed. It takes advantage of the kriging meta-modeling and importance sampling techniques. The proposed alternative estimator is finally applied to a finite element based structural reliability analysis.
Finding Exogenous Variables in Data with Many More Variables than Observations
Shimizu, Shohei, Washio, Takashi, Hyvarinen, Aapo, Imoto, Seiya
Many statistical methods have been proposed to estimate causal models in classical situations with fewer variables than observations (p
Identifying Aspects for Web-Search Queries
Wu, F., Madhavan, J., Halevy, A.
Many web-search queries serve as the beginning of an exploration of an unknown space of information, rather than looking for a specific web page. To answer such queries effec- tively, the search engine should attempt to organize the space of relevant information in a way that facilitates exploration. We describe the Aspector system that computes aspects for a given query. Each aspect is a set of search queries that together represent a distinct information need relevant to the original search query. To serve as an effective means to explore the space, Aspector computes aspects that are orthogonal to each other and to have high combined coverage. Aspector combines two sources of information to compute aspects. We discover candidate aspects by analyzing query logs, and cluster them to eliminate redundancies. We then use a mass-collaboration knowledge base (e.g., Wikipedia) to compute candidate aspects for queries that occur less frequently and to group together aspects that are likely to be semantically related. We present a user study that indicates that the aspects we compute are rated favorably against three competing alternatives related searches proposed by Google, cluster labels assigned by the Clusty search engine, and navigational searches proposed by Bing.
Regularizers for Structured Sparsity
Micchelli, Charles A., Morales, Jean M., Pontil, Massimiliano
We study the problem of learning a sparse linear regression vector under additional conditions on the structure of its sparsity pattern. This problem is relevant in machine learning, statistics and signal processing. It is well known that a linear regression can benefit from knowledge that the underlying regression vector is sparse. The combinatorial problem of selecting the nonzero components of this vector can be "relaxed" by regularizing the squared error with a convex penalty function like the $\ell_1$ norm. However, in many applications, additional conditions on the structure of the regression vector and its sparsity pattern are available. Incorporating this information into the learning method may lead to a significant decrease of the estimation error. In this paper, we present a family of convex penalty functions, which encode prior knowledge on the structure of the vector formed by the absolute values of the regression coefficients. This family subsumes the $\ell_1$ norm and is flexible enough to include different models of sparsity patterns, which are of practical and theoretical importance. We establish the basic properties of these penalty functions and discuss some examples where they can be computed explicitly. Moreover, we present a convergent optimization algorithm for solving regularized least squares with these penalty functions. Numerical simulations highlight the benefit of structured sparsity and the advantage offered by our approach over the Lasso method and other related methods.
The Complexity of Integer Bound Propagation
Bordeaux, L., Katsirelos, G., Narodytska, N., Vardi, M. Y.
Bound propagation is an important Artificial Intelligence technique used in Constraint Programming tools to deal with numerical constraints. It is typically embedded within a search procedure (branch and prune) and used at every node of the search tree to narrow down the search space, so it is critical that it be fast. The procedure invokes constraint propagators until a common fixpoint is reached, but the known algorithms for this have a pseudo-polynomial worst-case time complexity: they are fast indeed when the variables have a small numerical range, but they have the well-known problem of being prohibitively slow when these ranges are large. An important question is therefore whether strongly-polynomial algorithms exist that compute the common bound consistent fixpoint of a set of constraints. This paper answers this question. In particular we show that this fixpoint computation is in fact NP-complete, even when restricted to binary linear constraints.
Sufficient Component Analysis for Supervised Dimension Reduction
Yamada, Makoto, Niu, Gang, Takagi, Jun, Sugiyama, Masashi
The purpose of sufficient dimension reduction (SDR) is to find the low-dimensional subspace of input features that is sufficient for predicting output values. In this paper, we propose a novel distribution-free SDR method called sufficient component analysis (SCA), which is computationally more efficient than existing methods. In our method, a solution is computed by iteratively performing dependence estimation and maximization: Dependence estimation is analytically carried out by recently-proposed least-squares mutual information (LSMI), and dependence maximization is also analytically carried out by utilizing the Epanechnikov kernel. Through large-scale experiments on real-world image classification and audio tagging problems, the proposed method is shown to compare favorably with existing dimension reduction approaches.
Worst-Case Upper Bound for (1, 2)-QSAT
The rigorous theoretical analysis of the algorithm for a subclass of QSAT, i.e. (1, 2)-QSAT, has been proposed in the literature. (1, 2)-QSAT, first introduced in SAT'08, can be seen as quantified extended 2-CNF formulas. Until now, within our knowledge, there exists no algorithm presenting the worst upper bound for (1, 2)-QSAT. Therefore in this paper, we present an exact algorithm to solve (1, 2)-QSAT. By analyzing the algorithms, we obtain a worst-case upper bound O(1.4142m), where m is the number of clauses.
Design Patterns and Cross-Domain Analogies in Biologically Inspired Sustainable Design
Goel, Ashok K. (Georgia Institute of Technology) | Bras, Bert (Georgia Institute of Technology) | Helms, Michael (Georgia Institute of Technology) | Rugaber, Spencer (Georgia Institute of Technology) | Tovey, Craig (Georgia Institute of Technology) | Vattam, Swaroop (Georgia Institute of Technology) | Weissburg, Marc (Georgia Institute of Technology) | Wiltgen, Bryan (Georgia Institute of Technology) | Yen, Jeannette (Georgia Institute of Technology)
Sustainable design is as an important movement in design. Biologically inspired design is a major paradigm for sustainable design. In this paper, we analyze a corpus of biologically inspired design projects in terms of sustainability. We then describe a case study of analogical design of a fog harvesting net, and abstract from it the patterns of Hydrophobia and Hydrophilia. We indicate how these two function-mechanism design patterns occur in several design projects in our corpus. This analysis indicates how biologically inspired sustainable design can be analyzed in terms of cross-domain analogical transfer of design patterns.
Opportunities for AI to Improve Sustainable Building Design Processes
Haymaker, John R. (Design Process Innovation)
Sustainable building design is a complex social and technical process in which a broad range of stakeholders must construct and clearly communicate high quality design spaces. This paper summarizes recent assessments of current practice that illustrate how far industry today is from achieving this quality and clarity. Efforts to develop a platform of tools to address these limitations are discussed. PIP helps people communicate, share, and understand collaborative design processes; MACDADI helps project teams identify and manage rationale and consensus on decisions; Design Scenarios helps them generate requirements-driven alternative spaces, BIM, model-based analysis, and PIDO which helps to systematically assess these alternatives for their energy, daylight, structural, and cost impacts; and iRooms and the web, which help to communicate all of this information to engage designers, stakeholders, and decision makers in fast, multidisciplinary design and analysis processes. This new platform considerably improves the quality and clarity of AEC design spaces. However additional work would enable significant additional improvement. The paper concludes with a proposal for how AI might further improve the performance of this platform.