When you mention the strong differences, are you accounting for the y axis starting at varying locations? Once I realized this, the significance of the results went down significantly.
That's usually when you have some idea of the error in what you're measuring. They are just reporting on a social poll they did, isn't that usually a bit different. I mean of course this isn't a rigorous scientific study, but that doesn't mean it's useless either.
They're presenting averages, which should always be accompanied by the standard deviations, otherwise they're close to meaningless. I actually think box plots would be better here.
Indeed. It's hard to tell if any of the differences are significant, particularly when you compare with so many traits -- the chances of a false positive are very high.
I have a statistics final exam coming up; if the complete data set were available, I'd love to play with it for practice.
