Vitriolic Rant about “3D” Charts
By Tim Wilson on in Data Visualization, Excel with 3 Comments
This is my second week in a row in training — just today and tomorrow this week, thankfully. This week, the product is HardMetrics which, frankly, is a pretty damn cool tool. The trainer is the VP of Product Development, who has been architecting and developing in the reporting and analysis space for seven years or so.
HardMetrics actually OEMs a product from Visual Mining for their visual displays. And, there’s a lot of flexibility and power between the two products. However, I asked right off the bat if there was a way to disable the 3D effect from bar charts (there is). I’m not talking about three dimensions of data — just those damn annoying drop-shadows on two dimensions of data.
Below is an example of the 3D effect in a bar chart — quickly and effortlessly generated using Excel 2007.
These sorts of graphs make a southbound feller’s neck hair point due north. Hard! Unfortunately, Microsoft Excel makes it ridiculously easy to spit these charts out. And, as every BI vendor and data visualization tool maker has scrambled to be able to back up their Marketing departments’ claims that their tool will do “everything that you can do in Excel…and then some!” they’ve all gone right along and rolled out the same dastardly functionality.
The problem is: drop shadow adds NO value…AND can make the data harder to read! The reality is, dropping a shadow on a 2D picture is a fairly straightforward transformation. As a matter of fact, something very similar to that is one of the few homework exercises I remember from my C programming class in college (early 1990s).
The Hard Metrics VP who is doing the training admitted that dropping shadows are “eye candy” and help sell the product. That’s. Just. Ridiculous! Unfortunately, it’s also got the faint tingling jingle of truth.
Clearly illustrating data…and making it easy to clearly illustrate data…is what should sell products. If the supposed glitz of a drop shadow is the tipping point with a decision maker at a company, that’s a customer who is focussed on the wrong, wrong, WRONG thing, and, chances are, he/she is going to make other non-value-adding demands of the product. Of course, the real world requires generating revenue, and if there are potential customers who have cash in the bank that matches their misperceptions about best practices, then, well….
Check out the chart above. Quickly…estimate the revenue for Product A in July. Do it. Dont’ keep reading here. Scroll back up and make an estimate!
It looks to be a little more than $10 million, right? Wrong! It’s $10.8 million! Not only is this a 3D chart…but the bars are plopped down right in the middle of no-man’s land — check out the base of the graph. So, you actually have to project the shadow line back (diagonally and up) and then follow the plot over to the values on the left. That’s just silly. But, oh so easy to do in Excel. Thank you, Microsoft!
What absolutely kills me is that, in Excel, you at least have to consciously decide to add this obfuscating crap to a chart. Which too, too many dunderheads decide to do (all too often, I suspect, because they have a bunch of data and don’t know how to interpret it, so they spend extra time and energy making the chart fancier). The killer is that, in all too many analytics programs, this is the default! And, in some cases, it can’t be changed! This was the case with WebTrends OnDemand (sorry, WebTrends — I hate to pick on a solid tool that has a lot of positive features, but, in this regard, it talks, walks, and craps like a duck, so I’ve got to give it a quack out). These are people who should know better. It was a case of perception becoming reality — Marketing decided this was a “cool” feature that everyone else had and didn’t just stand up to not make it their de facto standard. Ugh!!!
Now, fortunately, as I was poking around on the ‘net for some good examples of this abomination…I hit some of the really big players in the BI space…and they had limited use of 3D in the screen caps they showed. I don’t know if that’s because the likes of Stephen Few, Edward Tufte, and the many good folk over at TDWI finally got it through their heads…or if I just hit the wrong pages. (DISCLAIMER: I have never seen Few’s or Tufte’s feelings on this specific subject — they’re two of the most brilliant minds in the visual presentation of data world, so I feel like I’m pretty safe by guessing that they’re not big fans.) It was an encouraging sign.
Some time…when I don’t have four baskets of laundry to fold, I’ll tell you what I really think about pie charts and — the horror! — 3D pie charts! Stay tuned.