Information Visualisation: Techniques, Usability and Evaluation
Ebad Banissi, Francis T. Marchese, Camilla Forsell, Jimmy Johansson
Language: English
Pages: 290
ISBN: 1443859818
Format: PDF / Kindle (mobi) / ePub
Author note: Ebad Banissi (Editor), Francis T. Marchese (Editor), Camilla Forsell (Editor), Jimmy Johansson (Editor)
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Information visualisation is the field of study that is concerned with the development of methods for transforming abstract, complex data into visual representations in order to make that data more easily communicable and understandable.
This volume reviews recent developments in information visualisation techniques, their application, and methods for their evaluation. It offers a wide range of examples of applied information visualisation from across disciplines such as history, art, the humanities, science and technology. Beginning with an examination of its medieval origins, it presents theoretical and applied approaches to information representation, including two and three-dimensional cartographic rendering and navigation techniques. In addition, it explores the language of shapes and how it can be employed to further the visualisation of multifaceted data. As a whole, this collection emphasises the important role that the visualisation process plays in extracting, analysing, and presenting the hidden layers of meaning found within large and complex data sets.
Topics and Features:
• Contributions from an international collection of researchers and authors.
• An introduction to the discipline of information visualisation, its current state of affairs, and its future trends.
• A discussion of information visualisation's origins, providing an important historical context for the field.
• A comprehensive review of methods for shaping and rendering two and three-dimensional representations of abstract information.
• The visualisation of interconnected networks of data in order to extract their causal relationships.
• An approach to hierarchical structuring and re-structuring of information by applying methods of two-dimensional data mapping.
• Application of common metaphors for visualizing computer code.
• Visualisation analysis of historical events and their relationships.
• A review of methods for evaluating information visualization tools, concepts, and methodologies, and recommendations for their application.
Potential drawbacks include: • • • Increased implementation effort, e.g. ensuring that relative sizes are preserved at the poles and equator. Occlusion, as information on the backside of the sphere is potentially hidden or possibly more difficult to use. Limitations – there have been a number of 3D info viz spheres in the past that have not been broadly adopted, probably due to limitations with spherical representations or interactions. As an example of the potential limitations of spheres,
various permutations of combinations. What are the attributes of shape? It is debatable which shape attributes to include in the working list of shape attributes (Fig 3.19). For example, early on, concavity seemed to be a potential attribute. Creating a matrix of possible attributes, using concavity as one attribute seemed promising. Fig. 3.19. Sample matrix exploring attributes of shape. In this example three attributes are considered: open/closed, dominant orientation (angle/square/curve),
in order of their occurrence along the polygon’s perimeter clockwise, and the vertex (xn, yn) is assumed to be the same as (x0, y0). The centroid of a nonself-intersecting closed polygon defined by n vertices (x0, y0), (x1, y1), ..., (xn-1, yn-1) is the point (Cx, Cy), where: and: where A is the polygon’s signed area and it is defined by the formula 90 Chapter Five Angular Treemaps algorithm The basic concept for generating polygonal subdivision is to use the weighted divide-and-conquer
96 Chapter Five Fig. 5.9. Application demonstration of file systems overview with boundary gaps feature. Colour saturation and edge thickness changes are used to assist when transferring from views of one level to another. For example, from overview (see Fig. 5.10(a)) to subfolder of “mp3” (see Fig. 5.10(b)) on a lower level, edges of the lower level nodes are thinner, and the colour of the lower level nodes are lighter than those of higher level nodes Navigation and Interaction A navigation
Next-Fit Algorithm [11], which is a solution to the Bin Packing Problem (Fig. 6.7). If the order of placement of the rectangles has been decided, the Next-Fit Algorithm offers a high-speed layout solution. In this algorithm, rectangles are filled from the upper left to the lower right of the Treemap. The algorithm places rectangles from top to bottom; if it cannot place a rectangle at the bottom, it draws a line on the right and continues placing rectangles on the line from the top. By repeatedly