That's really bush league (no pun intended). The one and only serious, scholarly and comprehensive dialect survey was started by the late Frederic Cassidy and is being continued by the qualified folks at the University of Wisconsin. Aside from the absurdities cited above, from what I've seen of this, the questions are leading and presuppose the respondents can actually *hear themselves; also there don't seem to be any qualifications (long-term residency, at least) established for the informants. And what's a 'double model?'

Thanks for bringing it to our attention, Bingley!