Creating more effective graphs

1. Introduction

What we mean by an effective group

General comments

Captions

The data we plot

2. Limitations of Some Common Charts and Graphs

Pie charts

Charts with a three-dimensional effect

Bar charts: stacked and grouped

Difference between curves

Bubble plots

3. Human Perception and Our Abiblity to Decode Graphs

Elementary graphical perception tasks

Ordered elementary tasks

Role of distance and detection

4. Some More Effective Graphs in One or Two Dimensions

Distribution of one variable

Strip plots

Dot plots

Histograms

Jittering

Comparing distributions: box plots

Relationship of two variables: scatterplots

Time series

Line graphs

Comments

5. Trellis Graphics and Other Ways to Display More Than Two Variables

Alternative presentations of three variables

Stacked bar chart

Labeled scatterplot

Trellis display

More than three variables

Superposed data sets

Trellis multipanel displays

Scatterplot matrices

Mosaic plots

Linked micromaps

Parallel coordinate plots

Nightingale rose

Financial plot

Comments

6. General Principles For Creating Effective Graphs

Terminology

Visual clarity

Clarity of data

Clarity of other elements

Clear understanding

General strategy

7. Scales

Aspect ratio: Banking to 45 ̕

Scales: must zero be included?

When to use logarithmic scales

Scale breaks

Using two Y scales

Data hidden in the scales

Other principles involving scales

8. Applying What We've Learned: Before and After Examples

Grouped bar chart

Ten small graphs

Radar chart

Multiple pie charts

Tables

9. Some Comments On Software

Statistical software: S Language

Drawing programs: Illustrator

Spreadsheets: Excel

Moving an Axis in Excel

Line charts with uneven time intervals

Dot charts from Excel

Data labels with Excel

10. Questions and Answers

1.) When should I use a table, and when should I use a graph?

2.) Should I use different graphs for presentations and for written reports?

3.) How do graphs for data analysis and graphs for communication differ?

4.) What should I use instead of pie charts?

5.) What if I just want an impression of the direction of the data? Then may I use three-dimensional charts?

6.) I use three-dimensional charts but I include data labels. That's OK, isn't it?

7.) I want my graphs to attract the reader's attention. How should I decorate them?

8.) Why do you think we see so many bad graphs?

9.) When should I use each type of graph?

Appendix A: Checklist of possible graph defects

Appendix B: List of figures with sources.