Data Viz Done Right

October 15, 2010

Many Eyes hurts my eyes

6 comments
The goal of Many 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).
Here is the second visualization create for this data set:


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.
I took this same data set (and added continent for filtering) and created this visualization with Tableau Public. You can download the Tableau Packaged Workbook here.

I had a few goals I wanted to accomplish. How did I do?
  1. Create a greater contrast between the colors in order to make those with the highest number of casualties stand out more.
  2. Convert the pie chart to a bar chart to make the comparisons easier to detect.
  3. Create a Pareto chart to highlight the most important set of factors.
  4. 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.
  5. Add a filter (at the top right) for Continent so that you can easily zoom in.
I have been having three problems publishing this workbook from Tableau Desktop 5.3 that maybe you can help me with. I don't recall running into these problems with 5.2.
  1. 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.
  2. The axis on the Pareto chart would not display the tick marks. It looks fine in Desktop.
  3. 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.
Very odd! Has anyone else run into these problems?

POST PUBLICATION NOTE: The blue-red color range has already changed to red only, even though I have yet to interact with the data.

6 comments :

  1. Andy,

    No, I don't agree with you. ManyEyes and Tableau are different. ManyEyes is for people who don't have too big knowledge about working with data and they want to create something very simply in just few minutes.

    Tableau = visualization software + a bit of Excel
    Tableau gives more possibilities but it is more difficult to use it.

    We have to remember that we are not alone in the internet :) There are many people with different knowledge, different education and they should have possibility to find simply software like ManyEyes to show interesting data.

    I use both ManyEyes and Tableau. I didn't have problems with learning how to use Tableau but it is not reason to show off, working with data is my profession.

    I will give you an example, I showed my tableau chart to a friend http://russiansphinx.blogspot.com/2010/08/geography-of-worlds-internet.html
    My friend was impressed but complaint that "it is so complicated, you should write to people how to use it, how to understand it". The chart is very simply, but some people feel lost when they have possibility to play with data, compare, analyse on their own. I am sure that the chart is not too complicated for you. Simply solutions are not worse.

    Btw, please don't write that using pie chart is a mistake, no, it's not. All world is 100% so no problem. It is interactive chart so you can place the mouse on the parts to learn more details. Yes I know that you prefer other types of charts.

    Yes colours on ManyEyes maps are scary, when you use text in place of data then it looks more normal like here http://russiansphinx.blogspot.com/2010/02/investment-climate-in-russian-regions_5991.html

    On ManyEyes, just like on Tableau, everyone can add their own data, if somebody has a wild imagination also can made up :) both software providers don't check sources of data.

    ReplyDelete
  2. NOTE: Reposted on behalf of Joe Mako. I somehow duplicated the blog post.

    Joe Mako said...
    The most recent release of Tableau Desktop that I know of is 5.2.4, see Release Notes

    Of note was you have two locations unrecognized, and plotted at (0,0).

    As for the color and axis issues, changed a couple of details and uploaded a remake.

    In this case, I set the calculate within option in the table calc to Country instead of Table Across or Down.

    I showed the header to sow the axis and tick marks, and changed the calculations a little, so now you can confirm that 80% of the casualties come for 20% of the countries.
    October 15, 2010 9:02 PM

    Joe Mako said...
    the web preview after publishing showed the colors correctly, but visiting in my webbrowser does not display the colors properly, nor do I see the reference lines.

    Have you contact Tableau about the bug yet?

    ReplyDelete
  3. Joe,

    I updated the workbook above with some of your suggestions.

    1. I fixed the references for Russian and Myanmar.

    2. You used circles in your Pareto, but I have used lines. I also kept the axis labels. I wonder if removing the axis labels is what caused the axis to disappear.

    3. I added the 80/20 reference lines. Thanks for the tip. It's funny how the 80/20 rules works nearly all the time.

    4. I will be contacting Tableau support regarding the issue of not retaining the colors.

    Thanks again!
    Andy

    ReplyDelete
  4. Hi Andy
    Nice post. I only see a Red-White palette using Firefox - not sure what you expect me to see, but there's no blue. Also, half the tiles of the world map are missing.

    Tableau bugs aside, this is an interesting post. I agree that ManyEyes is disappointing. It is a bug bear of mine that the Guardian Data Store, one of the best public data sources on the net, continues to create poor Many Eyes visualisations of their data. Their recent Quango post is a fine example - the blob charts are useless. Simon Rogers' response to me about this is that it's the best they can do in the short time they have available. I'd counter that it's better to have no viz at all than a poor one. (constructively - I like what those guys are doing!).

    While I agree with some of Russian Sphinx's opinions, I think that just because it's easier to make a substandard viz in Many Eyes than a top quality viz in Tableau does not make ManyEyes a better tool. Again, better no viz than a terrible one.

    And don't assume I think it's trivial to make an easy-to-use Tableau dashboard. It takes a lot of effort to make a slick dashboard in Tableau: one needs to know the tool inside out to make it work at its best.

    ReplyDelete
  5. Andy, I couldn't agree with you more. I would like to add that Many Eyes has the potential to do more harm than good to data visualization.

    ReplyDelete