INFORMATION MURALA technique for displaying and

navigating large information spaces

Dean F. Jerding and John T. StaskoGraphics, Visualization, and Usability Center

College of ComputingGeorgia Institute of Technology

MOTIVATION

Global visualizations for large data sets are constrained by the limited number of pixels on the screen

scalability problem addressed

WHAT IS INFORMATION MURAL ?

Information mural is a

– 2D, miniature representation– representing an entire information space– using visual attributes such as color and

intensity to portray information density

OBJECTIVES

Create a representation of a large information space on the screen

Mimic the original visual representation

Minimize the loss of information in the compressed view

AUTOMOBILE DATA

Standard parallel coordinate view of the data

AUTOMOBILE DATA

Mural of a parallel coordinate view of automobile data showing MPG, engine displacement, horsepower, weight, acceleration, and model year (1970 – 1982)

AUTOMOBILE DATA

Color overlaid for number of cylinders (3 = red, 4 = orange, 5 = yellow, 6 = green, 8 = cyan).

THE TECHNIQUE

First present the global view to the user

– Scale the original visualization– Make explicit the density of overlap of

information visually apparent (using colors)

Allow user to analyze or navigate the global view for detailed views on the items of interest

INFORMATION DENSITY REPRESENTATION

This is the distinguishing feature of this paper.

Problem – Many pixels on the original image contribute to a

single pixel in the mural– Each pixel in the mural can have a single color

Constraints– Cannot resort to using the RGB components

INFORMATION DENSITY REPRESENTATION

Some earlier approaches are – Aggregation– Sampling

SolutionColor the pixel according to the attribute

color that occurs most frequently in that pixel

THE BIGGER PICTURE

MURAL

ORIGINAL IMAGE

INTENSITY MAPPING(cont)

1. Construct a unit square connecting the centers of the surrounding four destination pixels

INTENSITY MAPPING (cont)

2. Using the scaled location of the center of the original pixel to divide the square into four quadrants

INTENSITY MAPPING (cont)

3. The area of the quadrant diagonally opposite to each of the four destination pixels is the amount of intensity contributed by that pixel

SUITABLE FOR ?

Navigating information spaces

Studying the characteristics of geographic/spatial data

Discovering attributes and relationships

A CLOSER LOOK……

Parallel program message trace diagram drawn by just overplotting

Mural of parallel program message trace

SUN SPOT MURAL

Mural of the number of sun spots recorded daily, 1850-1993.

SUN SPOT MURAL

Mural of the number of sun spots recorded daily, 1850-1993,

zoomed in on a small area

SUN SPOT MURAL

View of sun spots showing focus area and mural of entire data

set at the bottom.

DOCUMENT VISUALIZATION

DOCUMENT VISUALIZATION

                          

Murals showing keyword distribution for search on ``visualization'' (yellow), ``object-oriented'' (green), and ``OO'' (cyan) in three documents

OPINIONS A new approach to representing of data

density Examines all the points in the source image –

may be slower For very large data mural becomes fuzzy Colors - double edged sword

– helps in identifying strong patterns– noticing the colors – appropriateness of colors

HCI METRICS

User satisfaction - good Learning time - good User Performance } depends Error rate } on Retention } visualization

Thank you