Page 161 - Lean six sigma demystified

140 Lean Six Sigma DemystifieD

As Tufte would say, “Don’t let your charts become disinformation. There’s
enough of that in the world already.”

Chartjunk and Disinformation

Tufte reminds me about the need for clarity in all of the charts and graphs
we create, and their power to misinform. Lurking behind chartjunk is con-
tempt both for information and for the audience. Chartjunk promoters
imagine that numbers and details are boring, dull, and tedious, requiring
ornament to enliven. If the numbers are boring, then you’ve got the wrong
numbers.
Worse is contempt for our audience, designing as if readers were obtuse and
uncaring. In fact, consumers of graphics are often more intelligent about the infor-
mation at hand than those who fabricate the data decoration. Our readers may be
busy, but they are not stupid. Clarity and simplicity are completely opposite to
simple-mindedness.
Tufte argues that to make your information more usable, you will want to

• Document the source and characteristics of the data
• Insistently enforce appropriate comparisons
• Demonstrate the mechanisms of cause and effect
• Demonstrate cause and effect quantitatively
• Evaluate alternative explanations

Tufte argues for clarity and content over cuteness. Hence his term for any-
thing that violates these principles is chartjunk.

Dark Grid Lines Are Chartjunk

You can use Excel’s formatting capabilities to put boxes around cells, but they
may not reveal the structure of the data you want to highlight (Fig. 4-40).
Instead, you could choose to highlight the four trials (Fig. 4-41), or the three
temperatures (Fig. 4-42).

Chartjunk on Graphs

The same is true of Excel. If you draw a plain bar chart using Excel’s Chart
Wizard, you get a chart cluttered with unnecessary information: grid lines,
legends, background colors, and so on (Fig. 4-43).