Drexel University
Confidence-Aware Matrix Factorization for Recommender Systems
Wang, Chao (University of Science and Technology of China) | Liu, Qi (University of Science and Technology of China) | Wu, Runze (University of Science and Technology of China) | Chen, Enhong (University of Science and Technology of China) | Liu, Chuanren (Drexel University) | Huang, Xunpeng (University of Science and Technology of China) | Huang, Zhenya (University of Science and Technology of China)
Collaborative filtering (CF), particularly matrix factorization (MF) based methods, have been widely used in recommender systems. The literature has reported that matrix factorization methods often produce superior accuracy of rating prediction in recommender systems. However, existing matrix factorization methods rarely consider confidence of the rating prediction and thus cannot support advanced recommendation tasks. In this paper, we propose a Confidence-aware Matrix Factorization (CMF) framework to simultaneously optimize the accuracy of rating prediction and measure the prediction confidence in the model. Specifically, we introduce variance parameters for both users and items in the matrix factorization process. Then, prediction interval can be computed to measure confidence for each predicted rating. These confidence quantities can be used to enhance the quality of recommendation results based on Confidence-aware Ranking (CR). We also develop two effective implementations of our framework to compute the confidence-aware matrix factorization for large-scale data. Finally, extensive experiments on three real-world datasets demonstrate the effectiveness of our framework from multiple perspectives.
Reports on the 2017 AAAI Spring Symposium Series
Bohg, Jeannette (Max Planck Institute for Intelligent Systems) | Boix, Xavier (Massachusetts Institute of Technology) | Chang, Nancy (Google) | Churchill, Elizabeth F. (Google) | Chu, Vivian (Georgia Institute of Technology) | Fang, Fei (Harvard University) | Feldman, Jerome (University of California at Berkeley) | Gonzรกlez, Avelino J. (University of Central Florida) | Kido, Takashi (Preferred Networks in Japan) | Lawless, William F. (Paine College) | Montaรฑa, Josรฉ L. (University of Cantabria) | Ontaรฑรณn, Santiago (Drexel University) | Sinapov, Jivko (University of Texas at Austin) | Sofge, Don (Naval Research Laboratory) | Steels, Luc (Institut de Biologia Evolutiva) | Steenson, Molly Wright (Carnegie Mellon University) | Takadama, Keiki (University of Electro-Communications) | Yadav, Amulya (University of Southern California)
Reports on the 2017 AAAI Spring Symposium Series
Bohg, Jeannette (Max Planck Institute for Intelligent Systems) | Boix, Xavier (Massachusetts Institute of Technology) | Chang, Nancy (Google) | Churchill, Elizabeth F. (Google) | Chu, Vivian (Georgia Institute of Technology) | Fang, Fei (Harvard University) | Feldman, Jerome (University of California at Berkeley) | Gonzรกlez, Avelino J. (University of Central Florida) | Kido, Takashi (Preferred Networks in Japan) | Lawless, William F. (Paine College) | Montaรฑa, Josรฉ L. (University of Cantabria) | Ontaรฑรณn, Santiago (Drexel University) | Sinapov, Jivko (University of Texas at Austin) | Sofge, Don (Naval Research Laboratory) | Steels, Luc (Institut de Biologia Evolutiva) | Steenson, Molly Wright (Carnegie Mellon University) | Takadama, Keiki (University of Electro-Communications) | Yadav, Amulya (University of Southern California)
It is also important to remember that having a very sharp distinction of AI A rise in real-world applications of AI has stimulated for social good research is not always feasible, and significant interest from the public, media, and policy often unnecessary. While there has been significant makers. Along with this increasing attention has progress, there still exist many major challenges facing come a media-fueled concern about purported negative the design of effective AIbased approaches to deal consequences of AI, which often overlooks the with the difficulties in real-world domains. One of the societal benefits that AI is delivering and can deliver challenges is interpretability since most algorithms for in the near future. To address these concerns, the AI for social good problems need to be used by human symposium on Artificial Intelligence for the Social end users. Second, the lack of access to valuable data Good (AISOC-17) highlighted the benefits that AI can that could be crucial to the development of appropriate bring to society right now. It brought together AI algorithms is yet another challenge. Third, the researchers and researchers, practitioners, experts, data that we get from the real world is often noisy and and policy makers from a wide variety of domains.
Reports of the Workshops of the Thirty-First AAAI Conference on Artificial Intelligence
Anderson, Monica (University of Alabama) | Bartรกk, Roman (Charles University) | Brownstein, John S. (Boston Children's Hospital, Harvard University) | Buckeridge, David L. (McGill University) | Eldardiry, Hoda (Palo Alto Research Center) | Geib, Christopher (Drexel University) | Gini, Maria (University of Minnesota) | Isaksen, Aaron (New York University) | Keren, Sarah (Technion University) | Laddaga, Robert (Vanderbilt University) | Lisy, Viliam (Czech Technical University) | Martin, Rodney (NASA Ames Research Center) | Martinez, David R. (MIT Lincoln Laboratory) | Michalowski, Martin (University of Ottawa) | Michael, Loizos (Open University of Cyprus) | Mirsky, Reuth (Ben-Gurion University) | Nguyen, Thanh (University of Michigan) | Paul, Michael J. (University of Colorado Boulder) | Pontelli, Enrico (New Mexico State University) | Sanner, Scott (University of Toronto) | Shaban-Nejad, Arash (University of Tennessee) | Sinha, Arunesh (University of Michigan) | Sohrabi, Shirin (IBM T. J. Watson Research Center) | Sricharan, Kumar (Palo Alto Research Center) | Srivastava, Biplav (IBM T. J. Watson Research Center) | Stefik, Mark (Palo Alto Research Center) | Streilein, William W. (MIT Lincoln Laboratory) | Sturtevant, Nathan (University of Denver) | Talamadupula, Kartik (IBM T. J. Watson Research Center) | Thielscher, Michael (University of New South Wales) | Togelius, Julian (New York University) | Tran, So Cao (New Mexico State University) | Tran-Thanh, Long (University of Southampton) | Wagner, Neal (MIT Lincoln Laboratory) | Wallace, Byron C. (Northeastern University) | Wilk, Szymon (Poznan University of Technology) | Zhu, Jichen (Drexel University)
Reports of the Workshops of the Thirty-First AAAI Conference on Artificial Intelligence
Anderson, Monica (University of Alabama) | Bartรกk, Roman (Charles University) | Brownstein, John S. (Boston Children's Hospital, Harvard University) | Buckeridge, David L. (McGill University) | Eldardiry, Hoda (Palo Alto Research Center) | Geib, Christopher (Drexel University) | Gini, Maria (University of Minnesota) | Isaksen, Aaron (New York University) | Keren, Sarah (Technion University) | Laddaga, Robert (Vanderbilt University) | Lisy, Viliam (Czech Technical University) | Martin, Rodney (NASA Ames Research Center) | Martinez, David R. (MIT Lincoln Laboratory) | Michalowski, Martin (University of Ottawa) | Michael, Loizos (Open University of Cyprus) | Mirsky, Reuth (Ben-Gurion University) | Nguyen, Thanh (University of Michigan) | Paul, Michael J. (University of Colorado Boulder) | Pontelli, Enrico (New Mexico State University) | Sanner, Scott (University of Toronto) | Shaban-Nejad, Arash (University of Tennessee) | Sinha, Arunesh (University of Michigan) | Sohrabi, Shirin (IBM T. J. Watson Research Center) | Sricharan, Kumar (Palo Alto Research Center) | Srivastava, Biplav (IBM T. J. Watson Research Center) | Stefik, Mark (Palo Alto Research Center) | Streilein, William W. (MIT Lincoln Laboratory) | Sturtevant, Nathan (University of Denver) | Talamadupula, Kartik (IBM T. J. Watson Research Center) | Thielscher, Michael (University of New South Wales) | Togelius, Julian (New York University) | Tran, So Cao (New Mexico State University) | Tran-Thanh, Long (University of Southampton) | Wagner, Neal (MIT Lincoln Laboratory) | Wallace, Byron C. (Northeastern University) | Wilk, Szymon (Poznan University of Technology) | Zhu, Jichen (Drexel University)
The AAAI-17 workshop program included 17 workshops covering a wide range of topics in AI. Workshops were held Sunday and Monday, February 4-5, 2017 at the Hilton San Francisco Union Square in San Francisco, California, USA. This report contains summaries of 12 of the workshops, and brief abstracts of the remaining 5
Towards End-to-End Natural Language Story Generation Systems
Valls-Vargas, Josep (Drexel University) | Zhu, Jichen (Drexel University) | Ontaรฑรณn, Santiago (Drexel University)
Storytelling and story generation systems usually require knowledge about the story world to be encoded in some form of knowledge representation formalism, a notoriously time-consuming task requiring expertise in storytelling and knowledge engineering. In order to alleviate this authorial bottleneck, in this paper we propose an end-to-end computational narrative system that automatically extracts the necessary domain knowledge from corpus of stories written in natural language and then uses such domain knowledge to generate new stories. Specifically, we employ narrative information extraction techniques that can automatically extract structured representations from stories and feed those representations to an analogy-based story generation system. We present the structures we used to connect two existing computational narrative systems and report our experiments using a dataset of Russian fairy tales. Specifically we look at the perceived quality of the final natural language being generated and how errors in the pipeline affect the output.
Leveraging Multi-Layer Level Representations for Puzzle-Platformer Level Generation
Snodgrass, Sam (Drexel University) | Ontaรฑรณn, Santiago (Drexel University)
Procedural content generation via machine learning (PCGML) has been growing in recent years. However, many PCGML approaches are only explored in the context of linear platforming games, and focused on modeling structural level information. Previously, we developed a multi-layer level representation, where each layer is designed to capture specific level information. In this paper, we apply our multi-layer approach to Lode Runner, a game with non-linear paths and complex actions. We test our approach by generating levels for Lode Runner with a constrained multi-dimensional Markov chain (MdMC) approach that ensures playability and a standard MdMC sampling approach. We compare the levels sampled when using multi-layer representation against those sampled using the single-layer representation; we compare using both the constrained sampling algorithm and the standard sampling algorithm.
Studying the Effects of Training Data on Machine Learning-Based Procedural Content Generation
Snodgrass, Sam (Drexel University) | Summerville, Adam (University of California, Santa Cruz) | Ontanon, Santiago (Drexel University)
The exploration of Procedural Content Generation via Machine Learning (PCGML) has been growing in recent years. However, while the number of PCGML techniques and methods for evaluating PCG techniques have been increasing, little work has been done in determining how the quality and quantity of the training data provided to these techniques effects the models or the output. Therefore, little is known about how much training data would actually be needed to deploy certain PCGML techniques in practice. In this paper we explore this question by studying the quality and diversity of the output of two well-known PCGML techniques (multi-dimensional Markov chains and Long Short-term Memory Recurrent Neural Networks) in generating Super Mario Bros. levels while varying the amount and quality of the training data.
Single Believe State Generation for Handling Partial Observability with MCTS in StarCraft
Uriarte, Alberto (Drexel University) | Ontanon, Santiago (Drexel University)
A significant amount of work exists on handling partial observability for different game genres in the context of game tree search. However, most of those techniques do not scale up to RTS games. In this paper we present an experimental evaluation of a recently proposed technique, "single believe state generation," in the context of StarCraft. We evaluate the proposed approach in the context of a StarCraft playing bot and show that the proposed technique is enough to bring the performance of the bot close to the theoretical optimal where the bot can observe the whole game state.
Feature Selection for Learning from Demonstration in Minecraft
Packard, Brandon (Drexel University) | Ontanon, Santiago (Drexel University)
Learning from Demonstration has the potential to enable the crafting of behavior for non-player characters, allies, and enemies without requiring programming knowledge. This paper focuses on addressing two key problems of LfD when applied to games. The first is data sequentiality, when actions might be influenced by previous environmental states/actions, instead of just the current state. The second is having structured representations of data, where data is provided as an arbitrary number of predicates instead of a fixed-length vector. In this paper, we evaluate a collection of feature selection strategies to address these problems in the context case-based learning algorithms in the domain of Minecraft.