Oceania
Strategic Behaviour When Allocating Indivisible Goods
We survey some recent research regarding strategic behaviour in resource allocation problems, focusing on the fair division of indivisible goods. We consider a number of computational questions like how a single strategic agent misreports their preferences to ensure a particular outcome, and how agents compute a Nash equilibrium when they all act strategically. We also identify a number of future directions like dealing with non-additive utilities, and partial or probabilistic information about the preferences of other agents.
Efficient Spatio-Temporal Tactile Object Recognition with Randomized Tiling Convolutional Networks in a Hierarchical Fusion Strategy
Cao, Lele (Tsinghua University and The University of Melbourne) | Kotagiri, Ramamohanarao (The University of Melbourne) | Sun, Fuchun (Tsinghua University) | Li, Hongbo (Tsinghua University) | Huang, Wenbing (Tsinghua University) | Aye, Zay Maung Maung (The University of Melbourne)
Robotic tactile recognition aims at identifying target objects or environments from tactile sensory readings. The advancement of unsupervised feature learning and biological tactile sensing inspire us proposing the model of 3T-RTCN that performs spatio-temporal feature representation and fusion for tactile recognition. It decomposes tactile data into spatial and temporal threads, and incorporates the strength of randomized tiling convolutional networks. Experimental evaluations show that it outperforms some state-of-the-art methods with a large margin regarding recognition accuracy, robustness, and fault-tolerance; we also achieve an order-of-magnitude speedup over equivalent networks with pretraining and finetuning. Practical suggestions and hints are summarized in the end for effectively handling the tactile data.
A Joint Model for Entity Set Expansion and Attribute Extraction from Web Search Queries
Zhang, Zhenzhong (Institute of Software, Chinese Academy of Sciences) | Sun, Le (Institute of Software, Chinese Academy of Sciences) | Han, Xianpei (Institute of Software, Chinese Academy of Sciences)
Entity Set Expansion (ESE) and Attribute Extraction (AE) are usually treated as two separate tasks in Information Extraction (IE). However, the two tasks are tightly coupled, and each task can benefit significantly from the other by leveraging the inherent relationship between entities and attributes. That is, 1) an attribute is important if it is shared by many typical entities of a class; 2) an entity is typical if it owns many important attributes of a class. Based on this observation, we propose a joint model for ESE and AE, which models the inherent relationship between entities and attributes as a graph. Then a graph reinforcement algorithm is proposed to jointly mine entities and attributes of a specific class. Experimental results demonstrate the superiority of our method for discovering both new entities and new attributes.
Argument Mining from Speech: Detecting Claims in Political Debates
Lippi, Marco (University of Bologna) | Torroni, Paolo (University of Bologna)
The automatic extraction of arguments from text, also known as argument mining, has recently become a hot topic in artificial intelligence. Current research has only focused on linguistic analysis. However, in many domains where communication may be also vocal or visual, paralinguistic features too may contribute to the transmission of the message that arguments intend to convey. For example, in political debates a crucial role is played by speech. The research question we address in this work is whether in such domains one can improve claim detection for argument mining, by employing features from text and speech in combination. To explore this hypothesis, we develop a machine learning classifier and train it on an original dataset based on the 2015 UK political elections debate.
Numerical Relation Extraction with Minimal Supervision
Madaan, Aman (Visa Inc.) | Mittal, Ashish (IBM Research) | Mausam, . (Indian Institute of Technology Delhi) | Ramakrishnan, Ganesh (Indian Institute of Technology Bombay) | Sarawagi, Sunita (Indian Institute of Technology Bombay)
We study a novel task of numerical relation extraction with the goal of extracting relations where one of the arguments is a number or a quantity ( e.g., atomic_number(Aluminium, 13), inflation_rate(India, 10.9%)). This task presents peculiar challenges not found in standard IE, such as the difficulty of matching numbers in distant supervision and the importance of units. We design two extraction systems that require minimal human supervision per relation: (1) NumberRule, a rule based extractor, and (2) NumberTron, a probabilistic graphical model. We find that both systems dramatically outperform MultiR, a state-of-the-art non-numerical IE model, obtaining up to 25 points F-score improvement.
Transfer Learning for Cross-Language Text Categorization through Active Correspondences Construction
Zhou, Joey Tianyi (Institute of High Performance Computing) | Pan, Sinno Jialin (Nanyang Technological University) | Tsang, Ivor W. (University of Technology) | Ho, Shen-Shyang (Nanyang Technological University)
Most existing heterogeneous transfer learning (HTL) methods for cross-language text classification rely on sufficient cross-domain instance correspondences to learn a mapping across heterogeneous feature spaces, and assume that such correspondences are given in advance. However, in practice, correspondences between domains are usually unknown. In this case, extensively manual efforts are required to establish accurate correspondences across multilingual documents based on their content and meta-information. In this paper, we present a general framework to integrate active learning to construct correspondences between heterogeneous domains for HTL, namely HTL through active correspondences construction (HTLA). Based on this framework, we develop a new HTL method. On top of the new HTL method, we further propose a strategy to actively construct correspondences between domains. Extensive experiments are conducted on various multilingual text classification tasks to verify the effectiveness of HTLA.
Graph-without-cut: An Ideal Graph Learning for Image Segmentation
Gao, Lianli (University of Electronic Science and Technology of China) | Song, Jingkuan (University of Trento) | Nie, Feiping (Northwestern Polytechnical University) | Zou, Fuhao (Huazhong University of Science and Technology) | Sebe, Nicu (University of Trento) | Shen, Heng Tao (The University of Queensland)
Graph-based image segmentation organizes the image elements into graphs and partitions an image based on the graph. It has been widely used and many promising results are obtained. Since the segmentation performance highly depends on the graph, most of existing methods focus on obtaining a precise similarity graph or on designing efficient cutting/merging strategies. However, these two components are often conducted in two separated steps, and thus the obtained graph similarity may not be the optimal one for segmentation and this may lead to suboptimal results. In this paper, we propose a novel framework, Graph-Without-Cut (GWC), for learning the similarity graph and image segmentations simultaneously. GWC learns the similarity graph by assigning adaptive and optimal neighbors to each vertex based on the spatial and visual information. Meanwhile, the new rank constraint is imposed to the Laplacian matrix of the similarity graph, such that the connected components in the resulted similarity graph are exactly equal to the region number. Extensive empirical results on three public data sets (i.e, BSDS300, BSDS500 and MSRC) show that our unsupervised GWC achieves state-of-the-art performance compared with supervised and unsupervised image segmentation approaches.
Query Answering with Inconsistent Existential Rules under Stable Model Semantics
Wan, Hai (Sun Yat-sen University) | Zhang, Heng (Huazhong University of Science and Technology) | Xiao, Peng (Sun Yat-sen University) | Huang, Haoran (Fudan University ) | Zhang, Yan (Western Sydney University)
Classical inconsistency-tolerant query answering relies on selecting maximal components of an ABox/database which are consistent with the ontology. However, some rules in ontologies might be unreliable if they are extracted from ontology learning or written by unskillful knowledge engineers. In this paper we present a framework of handling inconsistent existential rules under stable model semantics, which is defined by a notion called rule repairs to select maximal components of the existential rules. Surprisingly, for R-acyclic existential rules with R-stratified or guarded existential rules with stratified negations, both the data complexity and combined complexity of query answering under the rule repair semantics remain the same as that under the conventional query answering semantics. This leads us to propose several approaches to handle the rule repair semantics by calling answer set programming solvers. An experimental evaluation shows that these approaches have good scalability of query answering under rule repairs on realistic cases.
On the Minimum Differentially Resolving Set Problem for Diffusion Source Inference in Networks
Zhou, Chuan (Institute of Information Engineering, Chinese Academy of Sciences) | Lu, Wei-Xue (Academy of Mathematics and Systems Science, Chinese Academy of Sciences) | Zhang, Peng (University of Technology, Sydney) | Wu, Jia (Centre for Quantum Computation &) | Hu, Yue (Intelligent Systems, University of Technology, Sydney) | Guo, Li (Institute of Information Engineering, Chinese Academy of Sciences)
In this paper we theoretically study the minimum Differentially Resolving Set (DRS) problem derived from the classical sensor placement optimization problem in network source locating. A DRS of a graph G = ( V, E ) is defined as a subset S ⊆ V where any two elements in V can be distinguished by their different differential characteristic sets defined on S. The minimum DRS problem aims to find a DRS S in the graph G with minimum total weight Σ v∈S w ( v ). In this paper we establish a group of Integer Linear Programming (ILP) models as the solution. By the weighted set cover theory, we propose an approximation algorithm with the Θ(ln n ) approximability for the minimum DRS problem on general graphs, where n is the graph size.
Direct Discriminative Bag Mapping for Multi-Instance Learning
Wu, Jia (University of Technology Sydney) | Pan, Shirui (University of Technology Sydney) | Zhang, Peng (University of Technology Sydney) | Zhu, Xingquan (Florida Atlantic University)
Multi-instance learning (MIL) is useful for tackling labeling ambiguity in learning tasks, by allowing a bag of instances to share one label. Recently, bag mapping methods, which transform a bag to a single instance in a new space via instance selection, have drawn significant attentions. To date, most existing works are developed based on the original space, i.e., utilizing all instances for bag mapping, and instance selection is indirectly tied to the MIL objective. As a result, it is hard to guarantee the distinguish capacity of the selected instances in the new bag mapping space for MIL. In this paper, we propose a direct discriminative mapping approach for multi-instance learning (MILDM), which identifies instances to directly distinguish bags in the new mapping space. Experiments and comparisons on real-world learning tasks demonstrate the algorithm performance.