Education
Notes on a New Philosophy of Empirical Science
This book presents a methodology and philosophy of empirical science based on large scale lossless data compression. In this view a theory is scientific if it can be used to build a data compression program, and it is valuable if it can compress a standard benchmark database to a small size, taking into account the length of the compressor itself. This methodology therefore includes an Occam principle as well as a solution to the problem of demarcation. Because of the fundamental difficulty of lossless compression, this type of research must be empirical in nature: compression can only be achieved by discovering and characterizing empirical regularities in the data. Because of this, the philosophy provides a way to reformulate fields such as computer vision and computational linguistics as empirical sciences: the former by attempting to compress databases of natural images, the latter by attempting to compress large text databases. The book argues that the rigor and objectivity of the compression principle should set the stage for systematic progress in these fields. The argument is especially strong in the context of computer vision, which is plagued by chronic problems of evaluation. The book also considers the field of machine learning. Here the traditional approach requires that the models proposed to solve learning problems be extremely simple, in order to avoid overfitting. However, the world may contain intrinsically complex phenomena, which would require complex models to understand. The compression philosophy can justify complex models because of the large quantity of data being modeled (if the target database is 100 Gb, it is easy to justify a 10 Mb model). The complex models and abstractions learned on the basis of the raw data (images, language, etc) can then be reused to solve any specific learning problem, such as face recognition or machine translation.
Online Learning: Stochastic and Constrained Adversaries
Rakhlin, Alexander, Sridharan, Karthik, Tewari, Ambuj
Learning theory has largely focused on two main learning scenarios. The first is the classical statistical setting where instances are drawn i.i.d. from a fixed distribution and the second scenario is the online learning, completely adversarial scenario where adversary at every time step picks the worst instance to provide the learner with. It can be argued that in the real world neither of these assumptions are reasonable. It is therefore important to study problems with a range of assumptions on data. Unfortunately, theoretical results in this area are scarce, possibly due to absence of general tools for analysis. Focusing on the regret formulation, we define the minimax value of a game where the adversary is restricted in his moves. The framework captures stochastic and non-stochastic assumptions on data. Building on the sequential symmetrization approach, we define a notion of distribution-dependent Rademacher complexity for the spectrum of problems ranging from i.i.d. to worst-case. The bounds let us immediately deduce variation-type bounds. We then consider the i.i.d. adversary and show equivalence of online and batch learnability. In the supervised setting, we consider various hybrid assumptions on the way that x and y variables are chosen. Finally, we consider smoothed learning problems and show that half-spaces are online learnable in the smoothed model. In fact, exponentially small noise added to adversary's decisions turns this problem with infinite Littlestone's dimension into a learnable problem.
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.
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.
EAAI-10: The First Symposium on Educational Advances in Artificial Intelligence
desJardins, Marie (University of Maryland Baltimore County) | Sahami, Mehran (Stanford University) | Wagstaff, Kiri (Jet Propulsion Laboratory)
EAAI encourages the sharing of innovative educational approaches that convey or leverage AI and its many subfields, including robotics, machine learning, natural language, and computer vision. EAAI follows the successful 2008 Spring Symposium on "Using AI to Motivate Greater Participation in Computer Science" and the 2008 AAAI AI Education Colloquium. Fifty-five attendees formally registered for the event, but many other AAAI attendees also visited one or more EAAI events. EAAI is planned to become an annual event; EAAI-11 will be held in San Francisco on August 9-10, 2011, collocated with AAAI-11. The 2010 symposium included an invited talk, paper presentations, model AI assignments, a teaching and mentoring workshop, a best educational video award, and a robotics track.
The Case for Case-Based Transfer Learning
Klenk, Matthew (Navy Center for Applied Research in Artificial Intelligence) | Aha, David W. (Navy Center for Applied Research in Artificial Intelligence) | Molineaux, Matt (Knexus Research Corporation)
Case-based reasoning (CBR) is a problem-solving process in which a new problem is solved by retrieving a similar situation and reusing its solution. Transfer learning occurs when, after gaining experience from learning how to solve source problems, the same learner exploits this experience to improve performance and/or learning on target problems. In transfer learning, the differences between the source and target problems characterize the transfer distance. CBR can support transfer learning methods in multiple ways. We illustrate how CBR and transfer learning interact and characterize three approaches for using CBR in transfer learning: (1) as a transfer learning method, (2) for problem learning, and (3) to transfer knowledge between sets of problems. We describe examples of these approaches from our own and related work and discuss applicable transfer distances for each. We close with conclusions and directions for future research applying CBR to transfer learning.
An Introduction to Intertask Transfer for Reinforcement Learning
Taylor, Matthew E. (Lafayette College) | Stone, Peter (University of Texas at Austin)
Transfer learning has recently gained popularity due to the development of algorithms that can successfully generalize information across multiple tasks. This article focuses on transfer in the context of reinforcement learning domains, a general learning framework where an agent acts in an environment to maximize a reward signal. The goals of this article are to (1) familiarize readers with the transfer learning problem in reinforcement learning domains, (2) explain why the problem is both interesting and dif๏ฌcult, (3) present a selection of existing techniques that demonstrate different solutions, and (4) provide representative open problems in the hope of encouraging additional research in this exciting area.
U-Sem: Semantic Enrichment, User Modeling and Mining of Usage Data on the Social Web
Abel, Fabian, Celik, Ilknur, Hauff, Claudia, Hollink, Laura, Houben, Geert-Jan
With the growing popularity of Social Web applications, more and more user data is published on the Web everyday. Our research focuses on investigating ways of mining data from such platforms that can be used for modeling users and for semantically augmenting user profiles. This process can enhance adaptation and personalization in various adaptive Web-based systems. In this paper, we present the U-Sem people modeling service, a framework for the semantic enrichment and mining of people's profiles from usage data on the Social Web. We explain the architecture of our people modeling service and describe its application in an adult e-learning context as an example.
Online Learning: Beyond Regret
Rakhlin, Alexander, Sridharan, Karthik, Tewari, Ambuj
We study online learnability of a wide class of problems, extending the results of (Rakhlin, Sridharan, Tewari, 2010) to general notions of performance measure well beyond external regret. Our framework simultaneously captures such well-known notions as internal and general Phi-regret, learning with non-additive global cost functions, Blackwell's approachability, calibration of forecasters, adaptive regret, and more. We show that learnability in all these situations is due to control of the same three quantities: a martingale convergence term, a term describing the ability to perform well if future is known, and a generalization of sequential Rademacher complexity, studied in (Rakhlin, Sridharan, Tewari, 2010). Since we directly study complexity of the problem instead of focusing on efficient algorithms, we are able to improve and extend many known results which have been previously derived via an algorithmic construction.
The Jobs Puzzle: A Challenge for Logical Expressibility and Automated Reasoning
Shapiro, Stuart C. (State University New York at Buffalo)
The Jobs Puzzle, introduced in a book about automated reasoning, is a logic puzzle solvable by some "intelligent sixth graders," but the formalization of the puzzle by the authors was, according to them, "sometimes difficult and sometimes tedious." The puzzle thus presents a triple challenge: 1) formalize it in a non-difficult, non-tedious way; 2) formalize it in a way that adheres closely to the English statement of the puzzle; 3) have an automated general-purpose commonsense reasoner that can accept that formalization and solve the puzzle quickly. In this paper, I present and discuss three formalizations that are less difficult and less tedious than the original. However, none satisfy all three requirements as well as might be desired, and there are a significant number of automated reasoners that cannot solve the puzzle using any of the formalizations. So the Jobs Puzzle remains an interesting challenge.