I was caught between a pillow and a soft place this morning with a choice between a session on social media and the other a session on charting. But, as a fan of Edward Tufte, a legendary charting specialist, I couldn’t resist attending Naomi’s data visualization session.
She began the session by testing the room lighting to see if the colours on her presentation would show correctly on the screen, something I can appreciate having given presentations myself where a variety of colours ended up looking the same. It is something everyone should do particularly if you are presenting charts. If your labels, gridlines, or distinguishing chart features don’t show up, you might as well not do the presentation at all.
Here are just a few of my favorite points:
- The best chart is the one where the information is detected most quickly
- If perceiving the information is not important, then a pie chart is fine, e.g., when the chart is used as decoration
- The way you read a chart depends on which software you use and labeling the data points does not make a bad chart ok. See the chart below to see if you can determine what the data points are. Does the line match up with the front of the bar, the back of the bar, or neither!
- Graphs are to show relationships and trends, not exact numbers. If you need exact numbers, then use a table. Hence, bar charts do not need numbers.
- All bar graphs should start at zero because bars reflect length which has a zero.
- Alphabetical order is rarely the best way to order data.
- There is no substitute for colour.
- People know what number comes between 88 and 90 so you don’t need to label every point.
- When we use error bars, we often use 68%. But 68% makes sense in a table for self-calculation. Doesn’t 95% make more sense in a chart?
- Museums want to show data honestly and accurately. Corporations….. have other ideas. 🙂
Naomi presents in a style reflective of a professional statistics geek with tons of charts and examples and I got quite a kick of the morning session. She showed us a lot of tricks that I like to play on my colleagues such as having them guess chart values on really bad charts. She showed us a number of charts that I have never seen before and am now anxious to try. She showed many examples of bad charts turned good with just a couple minutes of work. She provided a set of notes that is probably the best set I have EVER come across. She suggested that though Edward Tufte is a charting genius, he is not the only expert in charting and she introduced us to William Cleveland, one of her favourite experts.
This slideshow highlights just a few of the huge range of charts that Naomi highlighted. You really need her commentary to see just how funny some of the charts are but I’m sure you’ll enjoy them anyways.
Conversition Strategies Social Media Research: By researchers, For researchers
- Edward Tufte: Sparklines: theory and practice (edwardtufte.com)
- Using Modern Data Visualization Methods in Business Reports (businessmanagement.suite101.com)
- 50 Free Web Apps to Make Beautiful Graphs (bestconstructionmanagementdegree.com)