October 15, 2010
Many Eyes hurts my eyesMany Eyes is to "democratize visualization and to enable a new social kind of data analysis." This is a fantastic goal, however, many of the options available to create visualizations are poorly used. Let's look at two examples.
The data used for these visualizations can be found here, but note that the source is unknown, so I have no idea if the data is reliable or not.
The trouble with critiquing a visualization is that sometimes there are so many problems you become overwhelmed. Here are just a few:
- A bar chart is a much better way to display this data than a pie. chart
- There are way too many data points in the pie chart. While pie charts should be avoided whenever possible, if you MUST use them, limit them to no more than three slices.
- The pie does not start at the 0 degree mark.
- The slices, while ordered descending, are shown counter clockwise. Why?
- The interactivity (click on the slices) provides no value (i.e., chart junk).
For the most part, this map is well done. Some thoughts:
- There needs to be bit more contrast through the colors.
- Iraq clearly stands out from the rest as it should. My focus goes immediately there.
- I like the shading of the countries in their entirety. This one feature of Tableau that I wish they would add as a standard choice. Yes, I know there are workarounds.
- I like the option to switch between the shaded countries and bubbles, but again, the color choice could be better.
- Create a greater contrast between the colors in order to make those with the highest number of casualties stand out more.
- Convert the pie chart to a bar chart to make the comparisons easier to detect.
- Create a Pareto chart to highlight the most important set of factors.
- Make the map and bar charts interactive. If you click or lasso (i.e., select multiple) on countries, the map and bar charts automatically filter each other and the countries are highlighted on the Pareto chart.
- Add a filter (at the top right) for Continent so that you can easily zoom in.
- When I first publish the workbook to Tableau Public, the blue-red color range looks exactly as I created it. However, once I interact with the Tableau Public workbook above (e.g., lasso several countries), the color range changes to red only; the blue converts to red.
- The axis on the Pareto chart would not display the tick marks. It looks fine in Desktop.
- Since the tick marks would not display, I decided to add reference lines. Again, those display perfectly in Desktop, but you can't see them in Public.
POST PUBLICATION NOTE: The blue-red color range has already changed to red only, even though I have yet to interact with the data.