This graphic from the New York Times magazine is bad data presented poorly (and reproduced poorly, by my camera phone):
It’s presented poorly because those blood stains are impossible to compare since you can’t discern their edges, and it appears they don’t taper toward the edges at the same rate. Maybe they simply resized one of them to get the relative size, which would be wrong. Anyway, if they cared about communicating the data they probably would have used real data in the first place. (You could also complain that a red speckle-cloud is unfriendly to some color-blind people.)
It’s bad data because it’s an online NYT reader survey, which — although it’s from the “research and analytics” department (and no, I’m not going to add “analytics” to my Windows dictionary) — represents unknown sample selection effects on an undefined population. In other words, who cares what they think?
A survey like that would be a start if it was the only way you had to answer an important or hard-to-measure issue, and if you clearly stated that it was likely unreliable. But in this case there is good, nationally-representative data on this very question. So if NYT Magazine wanted to inform its readers of something, they could have used this.
Here’s the good data — from the General Social Survey — in a graph that is at least a lot better: this is good data in a chart that’s easier to read accurately, includes a breakout by strength of opinion, and uses more accessible colors (click to enlarge).
I think the NYT Magazine graphics violations are not just dumb and annoying — here’s another post all about them — I think they harm the public good. Graphics like this spread ignorance and contribute to the perception that statistics – especially graphic statistics – are just an arbitrary way of manipulating people rather than a set of tools for exploring data and attempting to answer real questions. (If you want awesome real graphics, check out Healy and Moody’s Annual Review of Sociology paper.)
P.S., I wrote more about spanking here.