The concept is pretty simple:
1. There are three major American dialect areas which run through Ohio, with names and recognizable differences in pronunciations.
2. Ohio State linguists are running a survey of visitors to COSI in Columbus, because they want to get more of an all-ages selection than the classic telephone survey provides.
[Telephone surveys were usually targeted for geographic distribution and now show long-time residency — ie, landline possession.]
Unfortunately, The Columbus Dispatch manages to get every major fact about American dialects wrong. They get the names wrong. They fail to capitalize the names, for some reason. They even turn the cot/caught distinction into cut/caught. (Is it a typo, or a feature of the reporter’s speech?) Very possibly, this is an editor problem and not a reporter problem, or even a problem with spellchecker. But messing up the linguistic elements of an article on linguistics means everybody reading has been told misinformation.
Basically, here’s the three main things they’re talking about.
Northern, Northern Cities, or “The North” extends from New York along the Great Lakes and outward from there, and has a lot of sub-dialects. It’s pretty much all a product of the Northern Cities Shift, a phonetic shift of vowels that you can find described here. Midland is the classic American “broadcast accent”, related historically to settlers from the Midlands of the UK and conveniently also in a midland area of the US. (And it has tons of sub-dialects, too.) Southern likewise extends from the east coast over, has lots of sub-dialects, but has washed up into a lot of rural Southern Ohio — and of course we have plenty of households from further South who’ve moved here.
Inland North is Columbus and surrounding areas, the way most people reckon it. Ohio State linguists are basically trying to make the name for that become the name for most of Ohio’s dialect areas, displacing “Midland” to be used for only the flattest Midwest accents. So it’s a bit weird for them to use their individual term in a way that will get college kids in trouble if they take linguistics anywhere else besides OSU. But linguists are always pulling infighting stuff like this.
All the same, it’s difficult to believe that the researcher didn’t talk about the distinctive Columbus sub-dialects, because even the newspaper’s commenters start talking about it. (Listing “kee-oke” for Coke, which I haven’t heard before but can believe.)
Actually, this hobbyist’s map is probably one of the best out there. It corresponds more with my experienced reality, that is! However, linguistic maps are doomed to be ever-changing, thanks to settlement patterns.