Information and Knowledge Visualization

Information Visualization is essentially the study of representation of non-numeric data. This non-numeric data can be in the form of graphs, maps, text or tables. Developments in scientific visualization, knowledge visualization, visual design, information graphics, and data visualization all are included in the purview of information visualization.

History of Information Visualization

Information Visualization has its beginning towards the end of the 18th century with abstract information being represented visually. The emergence of graphical representations in the 1990s enabled proper manifestation of information visualization methodologies. George G. Robertson, Stuart K. Card, and Jock McKinley formed the term ‘information visualization.’

Information Visualization Methods and Tools

The methods adopted in information visualization include:
• Graph Drawing - This involves symmetric layout, spectral layout, tree layout, force-based layout, hierarchical layout, and orthogonal layout. Dots corresponding to the vertices, arcs to the edges, and arrows to the orientation of these edges are used in graph drawings.
• Hyperbolic Tree – Hyperbolic tree represents data that increase in progression.
• Color Alphabet – Color alphabet allows representation of a alphabets or character by a distinctive color.
• Tree mapping - In this method, tree structured data, like number of patients in different departments of a hospital, can be represented in the form of nested rectangles with areas proportional to their respective numbers. (i.e department having the most number of patients will be represented by the largest rectangle)
• Multidimensional Scaling (MDS) – MDS is extensively used for representing 3-dimensional visualizations. The classifications include: metric dimensional scaling, non-metric dimensional scaling, classical multidimensional scaling.
• Halo – The halo technique allows large objects to be viewed on small screens. This technique is extensively used in 3D video games.
• Problem Solving Environment (PSE) – This is a specialized method for solving definite problems, like engineering instrument design, generic problems and the like.
• Information Visualization Reference Model – Developed in 1999 by Ed Chi, this is used as a reference in information visualization.

Applications of Information Visualization

The applications of information visualization extend to manufacturing production control, scientific research, financial data analysis and market research, crime mapping, data mining, and digital libraries.
• Data mining – Data mining refers to the extraction of useful data from huge data bases. Enterprise resource Planning, financial analysis are practical applications of data mining.
• Crime mapping – Geographic Information System, (GIS) an application of information visualization, allow law enforcers to identify crime spots.
• Digital Libraries – This is one of the most popular applications of information visualization.