2008 Working Papers

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  • Publication
    Design and formal model of an event-driven and service-oriented architecture for the Mobile Tourist Information System TIP
    (Working Paper, Department of Computer Science, University of Waikato, 2008) Eschner, Lisa; Hinze, Annika
    This thesis introduces a new collaboration framework for context-aware services in a mobile environment enabling services to co-operate with several anonymous co-operation partners. We extend the current TIP design and architecture so that new services may easily be added to and co-operate with existing ones. Obsolete services may be replaced by new ones providing the same functionality. Services are de-coupled. Service co-operation is completely changed. This means that services react to the events they receive, irrespective of the events publishers. We also show how service-oriented and event-driven architectures may be combined maintaining their respective advantages. We introduce features of serviceoriented architectures to services co-operating via an eventbased middleware. We describe the formal model of a new system for mobile tourist information and the newly introduced features of the collaboration framework. Those features fundamentally change the way services communicate and cooperate.
  • Publication
    Trust-based recommendations for mobile tourists in TIP
    (Working Paper, Department of Computer Science, The University of Waikato, 2008) Quan, Qiu; Hinze, Annika
    Recommender systems aim to suggest to users items they would like. However, concerns about the reliability of information from unknown recommenders influences user acceptance. In this paper, we analyse trust-based recommendations for the tourist information system TIP. We believe that the recommender strategy is closely related to the information domain applied. So, the delivered trust-based tourist recommendations have combined peers’ ratings on sights, trust computations and geographical constraints. We create two trust propagation models to spread trust in the TIP community. Three Trust based and location-aware filtering algorithms are implemented. According to research on feasibilities of trust in recommendation fields, three collaborative filtering algorithms in TIP are improved by introducing the trust concept.
  • Publication
    Considering reachability when comparing data refinements
    (Working Paper, University of Waikato, Department of Computer Science, 2008-11-03) Reeves, Steve
    Adding considerations about reachability to the Logics of Specification Languages [1] chapter [2].
  • Publication
    Mining meaning from Wikipedia
    (Working Paper, University of Waikato, Department of Computer Science, 2008-09) Medelyan, Olena; Legg, Catherine; Milne, David N.; Witten, Ian H.
    Wikipedia is a goldmine of information; not just for its many readers, but also for the growing community of researchers who recognize it as a resource of exceptional scale and utility. It represents a vast investment of manual effort and judgment: a huge, constantly evolving tapestry of concepts and relations that is being applied to a host of tasks. This article provides a comprehensive description of this work. It focuses on research that extracts and makes use of the concepts, relations, facts and descriptions found in Wikipedia, and organizes the work into four broad categories: applying Wikipedia to natural language processing; using it to facilitate information retrieval and information extraction; and as a resource for ontology building. The article addresses how Wikipedia is being used as is, how it is being improved and adapted, and how it is being combined with other structures to create entirely new resources. We identify the research groups and individuals involved, and how their work has developed in the last few years. We provide a comprehensive list of the open-source software they have produced. We also discuss the implications of this work for the long-awaited semantic web.
  • Publication
    Metadata tools for institutional repositories
    (Working Paper, University of Waikato, Department of Computer Science, 2008-08) Nichols, David M.; Paynter, Gordon W.; Chan, Chu-Hsiang; Bainbridge, David; McKay, Dana; Twidale, Michael B.; Blandford, Ann
    Current institutional repository software provides few tools to help metadata librarians understand and analyse their collections. In this paper we compare and contrast metadata analysis tools that were developed simultaneously, but independently, at two New Zealand institutions during a period of national investment in research repositories: the Metadata Analysis Tool (MAT) at The University of Waikato, and the Kiwi Research Information Service (KRIS) at the National Library of New Zealand. The tools have many similarities: they are convenient, online, on-demand services that harvest metadata using OAI-PMH, they were developed in response to feedback from repository administrators, and they both help pinpoint specific metadata errors as well as generating summary statistics. They also have significant differences: one is a dedicated tool while the other is part of a wider access tool; one gives a holistic view of the metadata while the other looks for specific problems; one seeks patterns in the data values while the other checks that those values conform to metadata standards. Both tools work in a complementary manner to existing web-based administration tools. We have observed that discovery and correction of metadata errors can be quickly achieved by switching web browser views from the analysis tool to the repository interface, and back. We summarise the findings from both tools’ deployment into a checklist of requirements for metadata analysis tools.
  • Publication
    A review of the empirical studies of computer supported human-to-human communication
    (Working Paper, University of Waikato, Department of Computer Science, 2008-07) Masoodian, Masood
    This paper presents a review of the empirical studies of human-to-human communication which have been carried out over the last three decades. Although this review is primarily concerned with the empirical studies of computer supported human-to-human communication, a number of studies dealing with group work in non-computer-based collaborative environments, which form the basis of many of the empirical studies of the recent years in the area of CSCW, are also discussed. The concept of person and task spaces is introduced and then subsequently used to categorise the large volume of studies reported in this review. This paper also gives a comparative analysis of the findings of these studies, and draws a number of general conclusions to guide the design and evaluation of future CSCW systems.
  • Publication
    Learning from the past with experiment databases
    (Working Paper, University of Waikato, Department of Computer Science, 2008-06-24) Vanschoren, Joaquin; Pfahringer, Bernhard; Holmes, Geoffrey
    Thousands of Machine Learning research papers contain experimental comparisons that usually have been conducted with a single focus of interest, and detailed results are usually lost after publication. Once past experiments are collected in experiment databases they allow for additional and possibly much broader investigation. In this paper, we show how to use such a repository to answer various interesting research questions about learning algorithms and to verify a number of recent studies. Alongside performing elaborate comparisons and rankings of algorithms, we also investigate the effects of algorithm parameters and data properties, and study the learning curves and bias-variance profiles of algorithms to gain deeper insights into their behavior.
  • Publication
    Graph-RAT: Combining data sources in music recommendation systems
    (Working Paper, University of Waikato, Department of Computer Science, 2008-07-28) McEnnis, Daniel; Bainbridge, David
    The complexity of music recommendation systems has increased rapidly in recent years, drawing upon different sources of information: content analysis, web-mining, social tagging, etc. Unfortunately, the tools to scientifically evaluate such integrated systems are not readily available; nor are the base algorithms available. This article describes Graph-RAT (Graph-based Relational Analysis Toolkit), an open source toolkit that provides a framework for developing and evaluating novel hybrid systems. While this toolkit is designed for music recommendation, it has applications outside its discipline as well. An experiment—indicative of the sort of procedure that can be configured using the toolkit—is provided to illustrate its usefulness.
  • Publication
    Reviewing the understanding of the effects of spacing on children’s eye movements for on-screen reading
    (Working Paper, Department of Computer Science, University of Waikato, 2008-04) Vanderschantz, Nicholas
    This paper endeavors to consolidate current knowledge and empirical research concerning the use of typography for children’s on-screen reading. This paper is not intended as a full literature review but attempts to raise awareness of the areas required for future investigation. This evaluation indicates a significant gap in the literature of children’s on-screen reading and proposes a need for further investigations in typographical spacing. These future studies need to objectively consider children’s eye movements and the effect of screen based text presentation on children’s comprehension.
  • Publication
    Compositional synthesis of discrete event systems via synthesis equivalence
    (Working Paper, Department of Computer Science, University of Waikato, 2008-05-12) Malik, Robi; Flordal, Hugo
    A two-pass algorithm for compositional synthesis of modular supervisors for largescale systems of composed finite-state automata is proposed. The first pass provides an efficient method to determine whether a supervisory control problem has a solution, without explicitly constructing the synchronous composition of all components. If a solution exists, the second pass yields an over-approximation of the least restrictive solution which, if nonblocking, is a modular representation of the least restrictive supervisor. Using a new type of equivalence of nondeterministic processes, called synthesis equivalence, a wide range of abstractions can be employed to mitigate state-space explosion throughout the algorithm.
  • Publication
    Summary of the diary study: “Please feed the digital parrot”
    (Working Paper, University of Waikato, 2008-03-04) Schweer, Andrea
    This document summarises the findings of the diary study “Please feed the Digital Parrot” conducted in May 2007. The aim of this study was to collect real-world examples of remembering behaviour. We show the most interesting entries we collected, highlighting the kinds of information people wish to remember, the situations in which they wish to remember this information and how they go about remembering information. We discuss in which ways the findings deviate from our expectations and the implications of our observations for context-aware systems research and for future diary studies.
  • Publication
    Finding video on the web
    (Working Paper, University of Waikato, 2008-02) Cunningham, Sally Jo; Nichols, David M.
    At present very little is known about how people locate and view videos. This study draws a rich picture of everyday video seeking strategies and video information needs, based on an ethnographic study of New Zealand university students. These insights into the participants’ activities and motivations suggest potentially useful facilities for a video digital library.
  • Publication
    A tool for metadata analysis
    (Working Paper, University of Waikato, 2008-02) Nichols, David M.; Chan, Chu-Hsiang; Bainbridge, David; McKay, Dana; Twidale, Michael B.
    We describe a Web-based metadata quality tool that provides statistical descriptions and visualisations of Dublin Core metadata harvested via the OAI protocol. The lightweight nature of development allows it to be used to gather contextualized requirements and some initial user feedback is discussed.
  • Publication
    Proceedings of the Third Computing Women Congress (CWC 2008): Student papers
    (Working Paper, University of Waikato, 2008-02) Hinze, Annika; Schweer, Andrea; Hempstalk, Kathryn
    The Third Computing Women Congress was held at the University of Waikato, Hamilton, New Zealand from February 11th to 13th, 2008. The Computing Women Congress (CWC) is a Summer University for women in Computer Science. It is a meeting-place for female students, academics and professionals who study or work in Information Technology. CWC provides a forum to learn about and share the latest ideas of computing related topics in a supportive environment. CWC provides an open, explorative learning and teaching environment. Experimentation with new styles of learning is encouraged, with an emphasis on hands-on experience and engaging participatory techniques.