Government
A Perspective on AI Research in India
The second was the propensity of the computing industry toward more lucrative assignments in the service sector. Both these factors are changing, not least because leading international software companies have set up research and development centers in the country. Computer science education established itself in India in the early 1980s when the Indian Institutes of Technology (IITs) set up computer science departments and started offering undergraduate programs in the discipline. Research in artificial intelligence took off soon afterward when the government of India launched the Knowledge Based Computing Systems (KBCS) program in conjunction with the United Nations Development Program (Saint-Dizier 1991). A number of nodal centers were set up to focus on different areas of research including expert systems (IIT Madras), speech processing (Tata Institue of Fundamental Research), parallel processing (Indian Institute for Science), image processing (Indian Statistical Institute), and natural language processing (Center for Development of Advanced Computing).
Reports of the AAAI 2011 Conference Workshops
Agmon, Noa (University of Texas at Austin) | Agrawal, Vikas (Infosys Labs) | Aha, David W. (Naval Research Laboratory) | Aloimonos, Yiannis (University of Maryland, College Park) | Buckley, Donagh (EMC) | Doshi, Prashant (University of Georgia) | Geib, Christopher (University of Edinburgh) | Grasso, Floriana (University of Liverpool) | Green, Nancy (University of North Carolina Greensboro) | Johnston, Benjamin (University of Technology, Sydney) | Kaliski, Burt (VeriSign, Inc.) | Kiekintveld, Christopher (University of Texas at El Paso) | Law, Edith (Carnegie Mellon University) | Lieberman, Henry (Massachusetts Institute of Technology) | Mengshoel, Ole J. (Carnegie Mellon University) | Metzler, Ted (Oklahoma City University) | Modayil, Joseph (University of Alberta) | Oard, Douglas W. (University of Maryland, College Park) | Onder, Nilufer (Michigan Technological University) | O' (University College Cork) | Sullivan, Barry (Cognitive Systems Research Insitute) | Pastra, Katerina (McGill University) | Precup, Doina (Stottler Henke Associates, Inc.) | Ramachandran, Sowmya (University of Dundee) | Reed, Chris (Istanbul Technical University) | Sariel-Talay, Sanem (Carnegie Mellon University) | Selker, Ted (Infosys Technologies Ltd.) | Shastri, Lokendra (Carnegie Mellon University) | Smith, Stephen F. (University of Michigan at Ann Arbor) | Singh, Satinder (University of Wisconsin, Madison) | Srivastava, Siddharth (University of Central Florida) | Sukthankar, Gita (Naval Research Laboratory) | Uthus, David C. (University of Technology, Sydney) | Williams, Mary-Anne
The AAAI-11 workshop program was held Sunday and Monday, August 7โ18, 2011, at the Hyatt Regency San Francisco in San Francisco, California USA. The AAAI-11 workshop program included 15 workshops covering a wide range of topics in artificial intelligence. The titles of the workshops were Activity Context Representation: Techniques and Languages; Analyzing Microtext; Applied Adversarial Reasoning and Risk Modeling; Artificial Intelligence and Smarter Living: The Conquest of Complexity; AI for Data Center Management and Cloud Computing; Automated Action Planning for Autonomous Mobile Robots; Computational Models of Natural Argument; Generalized Planning; Human Computation; Human-Robot Interaction in Elder Care; Interactive Decision Theory and Game Theory; Language-Action Tools for Cognitive Artificial Agents: Integrating Vision, Action and Language; Lifelong Learning; Plan, Activity, and Intent Recognition; and Scalable Integration of Analytics and Visualization. This article presents short summaries of those events.
Reports of the AAAI 2011 Fall Symposia
Blisard, Sam (Naval Research Laboratory) | Carmichael, Ted (University of North Carolina at Charlotte) | Ding, Li (University of Maryland, Baltimore County) | Finin, Tim (University of Maryland, Baltimore County) | Frost, Wende (Naval Research Laboratory) | Graesser, Arthur (University of Memphis) | Hadzikadic, Mirsad (University of North Carolina at Charlotte) | Kagal, Lalana (Massachusetts Institute of Technology) | Kruijff, Geert-Jan M. (German Research Center for Artificial Intelligence) | Langley, Pat (Arizona State University) | Lester, James (North Carolina State University) | McGuinness, Deborah L. (Rensselaer Polytechnic Institute) | Mostow, Jack (Carnegie Mellon University) | Papadakis, Panagiotis (University of Sapienza, Rome) | Pirri, Fiora (Sapienza University of Rome) | Prasad, Rashmi (University of Wisconsin-Milwaukee) | Stoyanchev, Svetlana (Columbia University) | Varakantham, Pradeep (Singapore Management University)
The Association for the Advancement of Artificial Intelligence was pleased to present the 2011 Fall Symposium Series, held Friday through Sunday, November 4โ6, at the Westin Arlington Gateway in Arlington, Virginia. The titles of the seven symposia are as follows: (1) Advances in Cognitive Systems; (2) Building Representations of Common Ground with Intelligent Agents; (3) Complex Adaptive Systems: Energy, Information and Intelligence; (4) Multiagent Coordination under Uncertainty; (5) Open Government Knowledge: AI Opportunities and Challenges; (6) Question Generation; and (7) Robot-Human Teamwork in Dynamic Adverse Environment. The highlights of each symposium are presented in this report.
Alternating Projections for Learning with Expectation Constraints
Bellare, Kedar, Druck, Gregory, McCallum, Andrew
We present an objective function for learning with unlabeled data that utilizes auxiliary expectation constraints. We optimize this objective function using a procedure that alternates between information and moment projections. Our method provides an alternate interpretation of the posterior regularization framework (Graca et al., 2008), maintains uncertainty during optimization unlike constraint-driven learning (Chang et al., 2007), and is more efficient than generalized expectation criteria (Mann & McCallum, 2008). Applications of this framework include minimally supervised learning, semisupervised learning, and learning with constraints that are more expressive than the underlying model. In experiments, we demonstrate comparable accuracy to generalized expectation criteria for minimally supervised learning, and use expressive structural constraints to guide semi-supervised learning, providing a 3%-6% improvement over stateof-the-art constraint-driven learning.
Effects of Treatment on the Treated: Identification and Generalization
Many applications of causal analysis call for assessing, retrospectively, the effect of withholding an action that has in fact been implemented. This counterfactual quantity, sometimes called "effect of treatment on the treated," (ETT) have been used to to evaluate educational programs, critic public policies, and justify individual decision making. In this paper we explore the conditions under which ETT can be estimated from (i.e., identified in) experimental and/or observational studies. We show that, when the action invokes a singleton variable, the conditions for ETT identification have simple characterizations in terms of causal diagrams. We further give a graphical characterization of the conditions under which the effects of multiple treatments on the treated can be identified, as well as ways in which the ETT estimand can be constructed from both interventional and observational distributions.
Bayesian clustering in decomposable graphs
In this paper we propose a class of prior distributions on decomposable graphs, allowing for improved modeling flexibility. While existing methods solely penalize the number of edges, the proposed work empowers practitioners to control clustering, level of separation, and other features of the graph. Emphasis is placed on a particular prior distribution which derives its motivation from the class of product partition models; the properties of this prior relative to existing priors is examined through theory and simulation. We then demonstrate the use of graphical models in the field of agriculture, showing how the proposed prior distribution alleviates the inflexibility of previous approaches in properly modeling the interactions between the yield of different crop varieties.
Hyperspectral Unmixing Overview: Geometrical, Statistical, and Sparse Regression-Based Approaches
Bioucas-Dias, Josรฉ M., Plaza, Antonio, Dobigeon, Nicolas, Parente, Mario, Du, Qian, Gader, Paul, Chanussot, Jocelyn
Imaging spectrometers measure electromagnetic energy scattered in their instantaneous field view in hundreds or thousands of spectral channels with higher spectral resolution than multispectral cameras. Imaging spectrometers are therefore often referred to as hyperspectral cameras (HSCs). Higher spectral resolution enables material identification via spectroscopic analysis, which facilitates countless applications that require identifying materials in scenarios unsuitable for classical spectroscopic analysis. Due to low spatial resolution of HSCs, microscopic material mixing, and multiple scattering, spectra measured by HSCs are mixtures of spectra of materials in a scene. Thus, accurate estimation requires unmixing. Pixels are assumed to be mixtures of a few materials, called endmembers. Unmixing involves estimating all or some of: the number of endmembers, their spectral signatures, and their abundances at each pixel. Unmixing is a challenging, ill-posed inverse problem because of model inaccuracies, observation noise, environmental conditions, endmember variability, and data set size. Researchers have devised and investigated many models searching for robust, stable, tractable, and accurate unmixing algorithms. This paper presents an overview of unmixing methods from the time of Keshava and Mustard's unmixing tutorial [1] to the present. Mixing models are first discussed. Signal-subspace, geometrical, statistical, sparsity-based, and spatial-contextual unmixing algorithms are described. Mathematical problems and potential solutions are described. Algorithm characteristics are illustrated experimentally.
The Discrete Infinite Logistic Normal Distribution
Paisley, John, Wang, Chong, Blei, David
We present the discrete infinite logistic normal distribution (DILN), a Bayesian nonparametric prior for mixed membership models. DILN is a generalization of the hierarchical Dirichlet process (HDP) that models correlation structure between the weights of the atoms at the group level. We derive a representation of DILN as a normalized collection of gamma-distributed random variables, and study its statistical properties. We consider applications to topic modeling and derive a variational inference algorithm for approximate posterior inference. We study the empirical performance of the DILN topic model on four corpora, comparing performance with the HDP and the correlated topic model (CTM). To deal with large-scale data sets, we also develop an online inference algorithm for DILN and compare with online HDP and online LDA on the Nature magazine, which contains approximately 350,000 articles.
The Complexity of Manipulating $k$-Approval Elections
An important problem in computational social choice theory is the complexity of undesirable behavior among agents, such as control, manipulation, and bribery in election systems. These kinds of voting strategies are often tempting at the individual level but disastrous for the agents as a whole. Creating election systems where the determination of such strategies is difficult is thus an important goal. An interesting set of elections is that of scoring protocols. Previous work in this area has demonstrated the complexity of misuse in cases involving a fixed number of candidates, and of specific election systems on unbounded number of candidates such as Borda. In contrast, we take the first step in generalizing the results of computational complexity of election misuse to cases of infinitely many scoring protocols on an unbounded number of candidates. Interesting families of systems include $k$-approval and $k$-veto elections, in which voters distinguish $k$ candidates from the candidate set. Our main result is to partition the problems of these families based on their complexity. We do so by showing they are polynomial-time computable, NP-hard, or polynomial-time equivalent to another problem of interest. We also demonstrate a surprising connection between manipulation in election systems and some graph theory problems.