let the data talk (ala llama maes keynote 2012)
TRANSCRIPT
LET THE DATA TALK
ALA Anaheim 2012
LLAMA – MAES
Cory Lown
Digital Technologies Development Librarian
North Carolina State University Libraries
16,500 BCE
6,200 BCE
950
1637
1786
1991
2005
Computers are useless. They can only give you answers.
— Pablo Picasso
Untitled Image Layout
• Image of something built
Untitled Image Layout
• Image of a tool
Psychophysics
The branch of psychology that studies the relationship between physical stimuli and mental response
Sti
mulus
Sti
mulation
Perception
9128732198432789543287
6784905043267812837698
7843928364382398731092
3478957438298374209123
0980934591283754845645
8934678238328009748349
9128732198432789543287
6784905043267812837698
7843928364382398731092
3478957438298374209123
0980934591283754845645
8934678238328009748349
Preattentive attributes
• Form– Orientation– Line length– Line width– Size– Shape– Curvature– Marks– Enclosure
• Color– Hue– Intensity
• Spatial Position– 2D
Preattentive attributes
• Form– Orientation– Line length– Line width– Size– Shape– Curvature– Marks– Enclosure
• Color– Hue– Intensity
• Spatial Position– 2D
Preattentive attributes
• Form– Orientation– Line length– Line width– Size– Shape– Curvature– Marks– Enclosure
• Color– Hue– Intensity
• Spatial Position– 2D
THINGS TO THINK ABOUTAdvice from Tufte & Few
“Above all else show the data”
– Edward Tufte
Tables & Graphs
Use Tables
When you will need to look up individual values
Use Tables
When you will need to compare individual values
Use Tables
When precise values are required
Use Graphs
When the message is contained in the shape of values
Use Graphs
When there is a large amount of data
Types of Graphs
Different quantitative relationships require different forms of graphs. There are heuristics you can follow.
Lines
Perfect for expressing change over time.
Points
When you want to show whether two things are correlated use points.
Bars
These are great for showing the rank of things.
Bars
Also good for expressing part to whole relationships -- percentages.
2D area
Use sparingly. This includes pie charts.
Highlight the data
Highlight the data by reducing non-data ink.
Be stingy with ink.
Highlight the data by reducing non-data ink.
If I removed this would the graph lose meaning?
Highlight the data by reducing non-data ink.
De-emphasize supporting components such as grid lines
Highlight the data by enhancing data ink.
Emphasize the most important data by using width, orientation, size, enclosure, hue, color intensity.
Highlight the data by enhancing data ink.
But don't overemphasize.
Organize
Group, prioritize, and sequence data to help viewers understand.
Too much data?
Try small multiples.
TOOLS
Untitled Image Layout
http://selection.datavisualization.ch/
READERS’ ADVISORY
Edward Tufte
The Visual Display of Quantitative Information
Stephen Few
Show Me the Numbers: Designing Tables and Graphs to Enlighten
Christopher Healey
Perception in Visualization
http://www.csc.ncsu.edu/faculty/healey/PP/
