Queensland University of Technology
Robustness of Bayesian Pool-Based Active Learning Against Prior Misspecification
Cuong, Nguyen Viet (National University of Singapore) | Ye, Nan (Queensland University of Technology) | Lee, Wee Sun (National University of Singapore)
We study the robustness of active learning (AL) algorithms against prior misspecification: whether an algorithm achieves similar performance using a perturbed prior as compared to using the true prior. In both the average and worst cases of the maximum coverage setting, we prove that all alpha-approximate algorithms are robust (i.e., near alpha-approximate) if the utility is Lipschitz continuous in the prior. We further show that robustness may not be achieved if the utility is non-Lipschitz. This suggests we should use a Lipschitz utility for AL if robustness is required. For the minimum cost setting, we can also obtain a robustness result for approximate AL algorithms. Our results imply that many commonly used AL algorithms are robust against perturbed priors. We then propose the use of a mixture prior to alleviate the problem of prior misspecification. We analyze the robustness of the uniform mixture prior and show experimentally that it performs reasonably well in practice.
Timed Probabilistic Automaton: A Bridge between Raven and Song Scope for Automatic Species Recognition
Duan, Shufei (Queensland University of Technology) | Zhang, Jinglan (Queensland University of Technology) | Roe, Paul (Queensland University of Technology) | Wimmer, Jason (Queensland University of Technology) | Dong, Xueyan (Queensland University of Technology) | Truskinger, Anthony (Queensland University of Technology) | Towsey, Michael (Queensland University of Technology)
Raven and Song Scope are two state-of-the-art automated sound analysis tools based on machine learning techniques for environmental monitoring. Many research works have been conducted upon them, however, no or rare exploration mentions about the performance and comparison between them. This paper compares the tools from six aspects: theory, software interface, ease of use, detection targets, detection accuracy, and potential applications. Through deep exploration one critical gap is identified that there is a lack of approach to detect both syllables and call structures, since Raven only aims to detect syllables while Song Scope targets call structures. Therefore, a Timed Probabilistic Automata (TPA) system is proposed which separates syllables and clusters them into complex structures.
Automata Modeling for Cognitive Interference in Users' Relevance Judgment
Zhang, Peng (The Robert Gordon University) | Song, Dawei (The Robert Gordon University) | Hou, Yuexian (Tianjin University) | Wang, Jun (Robert Gordon University) | Bruza, Peter (Queensland University of Technology)
Quantum theory has recently been employed to further advance thetheory of information retrieval (IR). A challenging research topicis to investigate the so called quantum-like interference in users'relevance judgment process, where users are involved to judge therelevance degree of each document with respect to a given query. Inthis process, users' relevance judgment for the current document isoften interfered by the judgment for previous documents, due to theinterference on users' cognitive status. Research from cognitivescience has demonstrated some initial evidence of quantum-likecognitive interference in human decision making, which underpins theuser's relevance judgment process. This motivates us to model suchcognitive interference in the relevance judgment process, which inour belief will lead to a better modeling and explanation of userbehaviors in relevance judgement process for IR and eventually leadto more user-centric IR models. In this paper, we propose to useprobabilistic automaton (PA) and quantum finite automaton (QFA),which are suitable to represent the transition of user judgmentstates, to dynamically model the cognitive interference when theuser is judging a list of documents.
Preface: Quantum Informatics for Cognitive, Social, and Semantic Processe
Bruza, Peter D. (Queensland University of Technology) | Lawless, William (Paine College) | Rijsbergen, Keith van (University of Glasgow) | Sofge, Donald A. (Naval Research Laboratory) | Widdows, Dominic (Google, Inc.)
While the application areas addressed typically - Social Interaction operate at a macroscopic scale and could not be considered quantum in a quantum mechanical sense, they may - Finance, economics, and social structures (e.g., organizations, share many key properties with quantum systems. Each paper was thoroughly reviewed by at problems with AI in non-quantum domains more efficiently least three members of the international programme committee. Kanerva (Stanford University), and an invited talk on day - Logic, planning, agents and multi-agent systems 2 by Terry Bollinger (ONR/MITRE). Finally, welcome and we look forward to a stimulating symposium!
Semantic Oscillations: Encoding Context and Structure in Complex Valued Holographic Vectors
Vine, Lance De (Queensland University of Technology) | Bruza, Peter (Queensland University of Technology)
In computational linguistics, information retrieval and applied cognition, words and concepts are often represented as vectors in high dimensional spaces computed from a corpus of text. These high dimensional spaces are often referred to as Semantic Spaces. We describe a novel and efficient approach to computing these semantic spaces via the use of complex valued vector representations. We report on the practical implementation of the proposed method and some associated experiments. We also briefly discuss how the proposed system relates to previous theoretical work in Information Retrieval and Quantum Mechanics and how the notions of probability, logic and geometry are integrated within a single Hilbert space representation. In this sense the proposed system has more general application and gives rise to a variety of opportunities for future research.
The Role of Non-Factorizability in Determining "Pseudo-Classical "Non-separability
Bruza, Peter (Queensland University of Technology) | Iqbal, Azhar (University of Adelaide) | Kitto, Kirsty (Queensland University of Technology)
This article introduces a "pseudo classical" notion of modelling non-separability. This form of non-separability can be viewed as lying between separability and quantum-like non-separability. Non-separability is formalized in terms of the non-factorizabilty of the underlying joint probability distribution. A decision criterium for determining the non-factorizability of the joint distribution is related to determining the rank of a matrix as well as another approach based on the chi-square-goodness-of-fit test. This pseudo-classical notion of non-separability is discussed in terms of quantum games and concept combinations in human cognition.
How Quantum Theory Is Developing the Field of Information Retrieval
Song, Dawei (The Robert Gordon University) | Lalmas, Mounia (University of Glasgow) | Rijsbergen, Keith van (University of Glasgow) | Frommholz, Ingo (University of Glasgow) | Piwowarski, Benjamin (University of Glasgow) | Wang, Jun (The Robert Gordon University) | Zhang, Peng (The Robert Gordon University) | Zuccon, Guido (University of Glasgow) | Bruza, Peter (Queensland University of Technology) | Arafat, Sachi (University of Glasgow) | Azzopardi, Leif (University of Glasgow) | Buccio, Emanuele Di (University of Padua) | Huertas-Rosero, Alvaro (University of Glasgow) | Hou, Yuexian (Tianjin University) | Melucci, Massimo (University of Padua) | Rueger, Stefan (The Open University)
Testing for the Non-Separability of Bi-Ambiguous Compounds
Kitto, Kirsty (Queensland University of Technology) | Ramm, Brentyn (Queensland University of Technology) | Bruza, Peter (Queensland University of Technology) | Sitbon, Laurianne (The University of Queensland)
Separability is a concept that is very difficult to define, and yet much of our scientific method is implicitly based upon the assumption that systems can sensibly be reduced to a set of interacting components. This paper examines the notion of separability in the creation of bi-ambiguous compounds that is based upon the CHSH and CH inequalities. It reports results of an experiment showing that violations of the CHSH and CH inequality can occur in human conceptual combination.