99 Problems But a Plot Ain't One of Them

Question 1

Polar coordinates:

When should you use polar coordinates?

(Two parts to the answer)

Answer 1

• Almost never.
• If you have a variable that is naturally circular.

Question 2

Polar coordinates:

A pie chart is most similar to what other kind of plot?

Answer 2

A bar plot.

Question 3

Polar coordinates:

Two data types when a polar plot might be helpful are:

Answer 3

• Time
• Compass direction

Question 4

Polar coordinates:

If you plot a histogram with polar coordinates, you get:

Answer 4

A rose plot

Question 5

Axis of evil:

Three common ways plots can be misleading are:

Answer 5

• Out of proportion
• Not having a full scale (no zero)
• Having two Y-axis values

Question 6

Axis of evil:

Rather than having two Y-axis values, it’s better to …

Answer 6

… use two different plots.

Question 7

Sensory overload:

The two basic measures of a good data visualization are:

Answer 7

1. What insights can somone get?
2. How quickly can they get the insight?

Often you need to get your message across in about 20 to 30 seconds.

Question 8

Sensory overload:

Four common (but bad) types of “charjunk” are:

Answer 8

1. Pictures
2. Skeuomorphism
3. Extra dimensions
4. Ostentatious colors or lines

Question 9

Sensory overload:

Skeuomorphism means …

Answer 9

Using reflections, shadows, etc.

(things that happen to real objects in the real world but don’t have a place in data visualization)

Question 10

Sensory overload:

If a plot uses stripes or hatching or some strange combinations of colors or fills, that’s typically called …

(and it’s not a good thing)

Answer 10

Ostentatious colors or lines

Question 11

Sensory overload:

It’s a good idea to use 3D plot effects …

Answer 11

… essentially never.