University of Bath
Automatic Model Selection in Subspace Clustering via Triplet Relationships
Yang, Jufeng (Nankai University) | Liang, Jie (Nankai University) | Wang, Kai (Nankai University) | Yang, Yong-Liang (University of Bath) | Cheng, Ming-Ming (Nankai University)
This paper addresses both the model selection (i.e., estimating the number of clusters K) and subspace clustering problems in a unified model. The real data always distribute on a union of low-dimensional sub-manifolds which are embedded in a high-dimensional ambient space. In this regard, the state-of-the-art subspace clustering approaches firstly learn the affinity among samples, followed by a spectral clustering to generate the segmentation. However, arguably, the intrinsic geometrical structures among samples are rarely considered in the optimization process. In this paper, we propose to simultaneously estimate K and segment the samples according to the local similarity relationships derived from the affinity matrix. Given the correlations among samples, we define a novel data structure termed the Triplet, each of which reflects a high relevance and locality among three samples which are aimed to be segmented into the same subspace. While the traditional pairwise distance can be close between inter-cluster samples lying on the intersection of two subspaces, the wrong assignments can be avoided by the hyper-correlation derived from the proposed triplets due to the complementarity of multiple constraints. Sequentially, we propose to greedily optimize a new model selection reward to estimate K according to the correlations between inter-cluster triplets. We simultaneously optimize a fusion reward based on the similarities between triplets and clusters to generate the final segmentation. Extensive experiments on the benchmark datasets demonstrate the effectiveness and robustness of the proposed approach.
Understanding Image Impressiveness Inspired by Instantaneous Human Perceptual Cues
Yang, Jufeng (Nankai University) | Sun, Yan (Nankai University) | Liang, Jie (Nankai University) | Yang, Yong-Liang (University of Bath) | Cheng, Ming-Ming (Nankai University)
With the explosion of visual information nowadays, millions of digital images are available to the users. How to efficiently explore a large set of images and retrieve useful information thus becomes extremely important. Unfortunately only some of the images can impress the user at first glance. Others that make little sense in human perception are often discarded, while still costing valuable time and space. Therefore, it is significant to identify these two kinds of images for relieving the load of online repositories and accelerating information retrieval process. However, most of the existing image properties, e.g., memorability and popularity, are based on repeated human interactions, which limit the research and application of evaluating image quality in terms of instantaneous impression. In this paper, we propose a novel image property, called impressiveness, that measures how images impress people with a short-term contact. This is based on an impression-driven model inspired by a number of important human perceptual cues. To achieve this, we first collect three datasets in various domains, which are labeled according to the instantaneous sensation of the annotators. Then we investigate the impressiveness property via six established human perceptual cues as well as the corresponding features from pixel to semantic levels. Sequentially, we verify the consistency of the impressiveness which can be quantitatively measured by multiple visual representations, and evaluate their latent relationships. Finally, we apply the proposed impressiveness property to rank the images for an efficient image recommendation system.
Reports of the AAAI 2016 Spring Symposium Series
Amato, Christopher (University of New Hampshire) | Amir, Ofra (Harvard University) | Bryson, Joanna (University of Bath) | Grosz, Barbara (Harvard University) | Indurkhya, Bipin (Jagiellonian University) | Kiciman, Emre (Microsoft Research) | Kido, Takashi (Rikengenesis) | Lawless, W. F. (Massachusetts Institute of Technology) | Liu, Miao (University of Southern California) | McDorman, Braden (Semio) | Mead, Ross (University of Amsterdam) | Oliehoek, Frans A. (University of Pennsylvania) | Specian, Andrew (American University in Paris) | Stojanov, Georgi (University of Electro-Communications) | Takadama, Keiki
The Association for the Advancement of Artificial Intelligence, in cooperation with Stanford University's Department of Computer Science, presented the 2016 Spring Symposium Series on Monday through Wednesday, March 21-23, 2016 at Stanford University. The titles of the seven symposia were (1) AI and the Mitigation of Human Error: Anomalies, Team Metrics and Thermodynamics; (2) Challenges and Opportunities in Multiagent Learning for the Real World (3) Enabling Computing Research in Socially Intelligent Human-Robot Interaction: A Community-Driven Modular Research Platform; (4) Ethical and Moral Considerations in Non-Human Agents; (5) Intelligent Systems for Supporting Distributed Human Teamwork; (6) Observational Studies through Social Media and Other Human-Generated Content, and (7) Well-Being Computing: AI Meets Health and Happiness Science.
Reports of the AAAI 2016 Spring Symposium Series
Amato, Christopher (University of New Hampshire) | Amir, Ofra (Harvard University) | Bryson, Joanna (University of Bath) | Grosz, Barbara (Harvard University) | Indurkhya, Bipin (Jagiellonian University) | Kiciman, Emre (Microsoft Research) | Kido, Takashi (Rikengenesis) | Lawless, W. F. (Massachusetts Institute of Technology) | Liu, Miao (University of Southern California) | McDorman, Braden (Semio) | Mead, Ross (University of Amsterdam) | Oliehoek, Frans A. (University of Pennsylvania) | Specian, Andrew (American University in Paris) | Stojanov, Georgi (University of Electro-Communications) | Takadama, Keiki
The Association for the Advancement of Artificial Intelligence, in cooperation with Stanford University's Department of Computer Science, presented the 2016 Spring Symposium Series on Monday through Wednesday, March 21-23, 2016 at Stanford University. The titles of the seven symposia were (1) AI and the Mitigation of Human Error: Anomalies, Team Metrics and Thermodynamics; (2) Challenges and Opportunities in Multiagent Learning for the Real World (3) Enabling Computing Research in Socially Intelligent Human-Robot Interaction: A Community-Driven Modular Research Platform; (4) Ethical and Moral Considerations in Non-Human Agents; (5) Intelligent Systems for Supporting Distributed Human Teamwork; (6) Observational Studies through Social Media and Other Human-Generated Content, and (7) Well-Being Computing: AI Meets Health and Happiness Science.
Patiency Is Not a Virtue: AI and the Design of Ethical Systems
Bryson, Joanna J. (University of Bath)
Here ought does require able--computationally and indeed logically intractable systems The question of Robot Ethics is difficult to resolve not because such as Asimov's laws are excluded (Myers, 2010). of the nature of Robots but because of the nature of What makes moral reasoning about intelligent artefacts Ethics. As with all normative considerations, robot ethics requires different from moral reasoning about natural entities is that that we decide what "really" matters--our most fundamental our obligations can be met not only through constructing the priorities. Are we more obliged to our biological socio-ethical system but also through specifications of the kin or to those with whom we share ideas? Do we value the artefacts. This is the definition of an artefact.
Computational Music Theory
Boenn, Georg (University of Glamorgan) | Brain, Martin (University of Oxford) | Vos, Marina De (University of Bath ) | Ffitch, John (University of Bath)
One of the goals of the study of music theory is to develop sets of rules to describe different styles of music. By formalising these rules so that their semantics are machine intelligible, it is possible to use computers to reason about and analyse these rules -- computational music theory. Anton is an automatic composition system based on this approach. It formalises the rules of Renaissance Counterpoint using AnsProlog and uses an answer set solver to compose pieces. This paper discusses Anton, presenting the ideas behind the system and focusing on the challenges of modelling and synthesising rhythm.
Context Transitions: User Identification and Comparison of Mobile Device Motion Data
Lovett, Tom (University of Bath and Vodafone) | O' (University of Bath) | Neill, Eamonn
In this paper, we study a time-critical facet of context-awareness: context transitions, which we model as changes in specific context types over time, e.g., activity or location. We present results from a user-centred field study involving participant interviews and motion data capture from two mobile device sensors: the accelerometer and magnetic field sensor. The results show how the participants subjectively interpret their daily context transitions with variable granularity, and a comparison of these context transitions with mobile device motion data shows how the motion data poorly reflect the identified transitions. The results imply that care should be taken when representing and modelling users’ subjective interpretations of context, as well as the objective nature of context sensors. Furthermore, processing and usability trade-offs should be made if real-time on-device transition detection is to be implemented.