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Now showing 1 - 7 of 7
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    When Size Matters: Towards Evaluating Perceivability of Choropleths
    (The Eurographics Association, 2018) McNabb, Liam; Laramee, Robert S.; Wilson, Max; {Tam, Gary K. L. and Vidal, Franck
    Choropleth maps are an invaluable visualization type for mapping geo-spatial data. One advantage to a choropleth map over other geospatial visualizations such as cartograms is the familiarity of a non-distorted landmass. However, this causes challenges when an area becomes too small in order to accurately perceive the underlying color. When does size matter in a choropleth map? We conduct an experiment to verify the relationship between choropleth maps, their underlying color map, and a user's perceivability. We do this by testing a user's perception of color relative to an administrative area's size within a choropleth map, as well as user-preference of fixed-locale maps with enforced minimum areas. Based on this initial experiment we can make the first recommendations with respect to a unit area's minimum size in order to be perceivably useful.
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    Cartograms with Topological Features
    (The Eurographics Association, 2018) Tong, Chao; McNabb, Liam; Laramee, Robert S.; {Tam, Gary K. L. and Vidal, Franck
    Cartograms are a popular and useful technique for depicting geo-spatial data. Dorling style and rectangular cartograms are very good for facilitating comparisons between unit areas. Each unit area is represented by the same shape such as a circle or rectangle, and the uniformity in shapes facilitates comparative judgment. However, the layout of these more abstract shapes may also simultaneously reduce the map's legibility and increase error. When we integrate univariate data into a cartogram, the recognizability of cartogram may be reduced. There is a trade-off between information recognition and geo-information accuracy. This is the inspiration behind the work we present. We attempt to increase the map's recognizability and reduce error by introducing topological features into the cartographic map. Our goal is to include topological features such as a river in a Dorling-style or rectangular cartogram to make the visual layout more recognizable, increase map cognition and reduce geospatial error. We believe that compared to the standard Dorling and rectangular style cartogram, adding topological features provides familiar geo-spatial cues and flexibility to enhance the recognizability of a cartogram.
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    GPU-Assisted Scatterplots for Millions of Call Events
    (The Eurographics Association, 2018) Rees, Dylan; Roberts, Richard C.; Laramee, Robert S.; Brookes, Paul; D'Cruze, Tony; Smith, Gary A.; {Tam, Gary K. L. and Vidal, Franck
    With four percent of the working population employed in call centers in both the United States and the UK, the contact center industry represents a sizable proportion of modern industrial landscapes. As with most modern industries, data collection is de rigueur, producing gigabytes of call records that require analysis. The scatterplot is a well established and understood form of data visualization dating back to the 17th century. In this paper we present an application for visualizing large call centre data sets using hardware-accelerated scatterplots. The application utilizes a commodity graphics card to enable visualization of a month's worth of data, enabling fast filtering of multiple attributes. Filtering is implemented using the Open Computing Language (OpenCL), providing significant performance improvement over traditional methods. We demonstrate the value of our application for exploration and analysis of millions of call events from a real-world industry partner. Domain expert feedback from our industrial partners is reported.
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    Towards a Survey of Interactive Visualization for Education
    (The Eurographics Association, 2018) Fırat, Elif E.; Laramee, Robert S.; {Tam, Gary K. L. and Vidal, Franck
    Graphic design and visualization are becoming fundamental components of education. The use of advanced visual design in pedagogy is growing and evolving rapidly. One of their aims is to enhance the educational process by facilitating better understanding of the subject with the use of graphical representation methods. Research papers in this field offer important opportunities to examine previously completed experiments and extract useful educational outcomes. This paper analyzes and classifies pedagogical visualization research papers to increase understanding in this area. To our knowledge, this is the first (work-in-progress) survey paper on advanced visualization for education. We categorize related research papers into original subject groups that enable researchers to compare related literature. Our novel classification enables researchers to find both mature and unexplored directions which can inform directions for future work. This paper serves as a valuable resource for both beginners and experienced researchers who are interested in interactive visualization for education.
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    SoS TextVis: A Survey of Surveys on Text Visualization
    (The Eurographics Association, 2018) Alharbi, Mohammad; Laramee, Robert S.; {Tam, Gary K. L. and Vidal, Franck
    Text visualization is a rapidly growing sub-field of information visualization and visual analytics. There are many approaches and techniques introduced every year to address a wide range of tasks and enable researchers from different disciplines to obtain leading-edge knowledge from digitized collections. This can be challenging particularly when the data is massive. Additionally, the sources of digital text have spread substantially in the last decades in various forms, such as web pages, blogs, twitter, email, electronic publications, and books. In response to the explosion of text visualization research literature, the first survey article was published in 2010. Furthermore, there are a growing number of surveys that review existing techniques and classify them based on text research methodology. In this work, we aim to present the first Survey of Surveys (SoS) that review all of the survey and state-of-the-art papers on text visualization techniques and provide an SoS classification. We study and compare the surveys, and categorize them into 5 groups: (1) document-centered, (2) user task analysis, (3) cross-disciplinary, (4) multifaceted, and (5) satellite-themed. We provide survey recommendations for researchers in the field of text visualization. The result is a very unique, valuable starting point and overview of the current state-of-the-art in text visualization research literature.
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    RiverState: A Visual Metaphor Representing Millions of Time-Oriented State Transitions
    (The Eurographics Association, 2018) Roberts, Richard C.; Rees, Dylan; Laramee, Robert S.; Brookes, Paul; Smith, Gary A.; {Tam, Gary K. L. and Vidal, Franck
    Developing a positive relationship between a business and its customers is vital to success. The outcome of any customer interaction can determine future patronage of the business. Many industry's only point of interaction with their customers is through a contact centre where everything from sales to complaints are handled. This places tremendous importance on the operational efficiency of the contact centre and the level of care provided to the customers. These customer interactions are recorded and archived in large databases, but undertaking insightful analysis is challenging due to both the size and complexity of the data. We present a visual solution to the tracking of customer interactions at a large scale. RiverState visualises the collective flow of callers through the process of interacting with a contact centre using a river metaphor. We use finite state transition machines with customised edges to depict millions of events and the states callers go through to complete their journey. We implement a range of novel features to enhance the analytical qualities of the application, and collect feedback from domain experts to analyse and evaluate the use of the software.
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    Spectrum: A C++ Header Library for Colour Map Management
    (The Eurographics Association, 2018) Roberts, Richard C.; McNabb, Liam; AlHarbi, Naif; Laramee, Robert S.; {Tam, Gary K. L. and Vidal, Franck
    The use of colour mapping is fundamental to visualisation research. It acts as an additional layer beyond rendering in the spatial dimensions and provides a link between values in any dataset. When designing and building visualisation research software, the process of creating and managing a colour mapping system can be time-consuming and complex. Existing alternatives offer niche features and require complex dependencies or installations. We present Spectrum; an open source colour map management library that is developer friendly with no installation required, and that offers a wide variety of features for the majority of use cases. We demonstrate the utility of the library through simple snippets of code and a number of examples which illustrate its ease of use and functionality, as well as a video demonstrating the installation and use of the library in under two minutes. It is a very valuable jump-start tool for developers and researchers who need to focus on other tasks.