Chapters six and seven of Information Dashboard Design talk about various considerations when putting a dashboard together--how the elements are percieved, what the best uses are for each, and how they work together to convey information.
Chapter Six
Display data based on the nature of the information, the nature of the message, and the needs and preferences of the audience.
Language is always understood serially--one word at a time.
The strength of written words and numbers is their precision. Numbers draw attention to individual numbers, but don't work good for comparisons of multiples and "bigger pictures".
Tables are good for looking up data.
Text is for values.
Graphs are for patterns.
Effective dashboards combine text and graphics to support meaning:
- What the viewer needs
- How the data is to be used
- What the message is
All of these are effected by:
- What is the best display
- What will fit in a small space
Six types of display--graphs, images, icons, objects, text, organizers.
Graphes are:
- bullet graphs--comparitive to goal
- bar graphs--start at goal, used for descrete instances, are better than pie charts for showing parts of a whole
- stacked bar graphs--effectively similar to small multiples, best to show contribution to a whole.
- combination graphs
- line graphs--used with intervals, emphasize continuity and progression, patters and change instead of values, do not need to start at zero.
- sparklines--for historical context only, not values.
- box plots--show high, medium, low
- scatter plots--show correlations
- tree maps--comparisons within hierarchies
Icons have three uses: to alert, to show up or down, to show on or off.
Ogranizers are tables, maps, and small multiples.
Chapter Seven
Dashboards must be easy to use and visually appealing.
Group items by business function and use.
- Minimal boarders
- Keep groups together
- Support meaningful comparisons
- Discourage meaningless comparisons
"When organizing data on a dashboard, start by learning precisely how the information will be used and how the pieces ought to be arranged to best serve these uses." (p. 164)
"Measures of performance come alive only when you compare them to other measures." (p. 165)
Encourage comparisons by:
- combining items in a single table or graph
- placing items close to one another
- linking items with color
- use comparitive values (ratios, percents, etc.)
"Anything that means the same thing or functions the same way ought to look the same...aesthetically pleasing dashboards are more enjoyable, which makes them more relaxing, which prepares the viewer for greater insight and creative response...aesthetics, when not in conflict with a product's usability, possesses intrinsic qualities that also contribute to usability." (p. 168)
Keep bright colors to a minimum, except when highlighting
Use less satuated colors, except when highlighting
Use pale background colors
Use legible text fonts
Use consistent action items.
Only the user can judge if the design is effective.