The SEO Lie Factor
One of my current projects has the goal of creating a series of charts and graphs that would allow my SEO team to intelligently show progress of client projects. Sure we could, just like everyone else, show rankings and traffic, but I'm looking for creative ways to combine data to provide deeper insight. This got me to thinking about the lies often associated with SEO statistics.
The trick with graphs is displaying accurate information. That goes beyond just using accurate numbers to power the graphics. It also involves looking at the end result with a critical eye and asking, “How might someone misinterpret this?” While thinking about this I've come to the conclusion that 3D graphs, although pretty, are the most likely to result in false impressions.
Take for instance the common 3D pie chart I've shown below.
What is your first impression about the % of traffic coming from Google (blue pie piece)? You're probably inclined to say that the percentage for Google is about double that of Yahoo and MSN. That impression is a result of my use of a 3D perspective which I purposefully manipulated to inflate Google. The underlying data though has Google at 0.3% with both Yahoo and MSN at 0.35%. The data is accurate, but my portrayal of it is deceiving.
Here's another example using columns.
This time around I adjusted the perspective and put MSN up front to make it look like MSN delivers what looks like almost 3 times the traffic of Google. Using a non-zero scale also amplifies the perception of MSN's dominance. Again the underlying data has Google at 0.3% and both Yahoo and MSN at 0.35%. Anyone quickly glancing at this graph would surely be tricked in to believing that MSN is a much more important player than it actually is.
Edward R. Tufte, the author of The Visual Display of Quantitative Information calls this the Lie Factor and even provides a simple formula for calculating it:
Lie Factor = size of effect shown in graph / size of effect in data x 100
In my first chart the the lie factor is 6 and in my second chart the lie factor is 2. For reference, Tufte says that, “a lie factor greater than 1.05 or less than 0.95 indicates a substantial distortion, far beyond minor inaccuracies.”
I used to favor 3D graphs in the past up until a client came right out and said to me that one I had created was confusing. I realized at that point that “confusing, but pretty” just isn't a good combination and I've been on the 2D graph bandwagon ever since. However, it's only during my most recent efforts to create new ways of visualizing SEO project performance that I've thought about the many ways that people create deceptive charts and graphs. Whether you're doing SEO in-house or using the services of an SEO agency, beware of the lie factor. That is, unless you're one of my clients in which case just nod your head and pat me on the back for a job well done!