Nope, its actually a correlation of 0. All the people who didn't get diabetes had the same DHMO consumption. If you want to be snarky, do try to at least make sense.
No, the R^2 is 1.0 between (dhmo-exposure,got-diabetes). You're talking about (dhmo-exposure,!got-diabetes) which turns out to also have a 1.0 correlation, which was kind of the point of my snark in the first place.
Those who don't understand even the basics of correlation are doomed to be led astray by statistics. The authors of the paper in question seem to understand it just fine, it would be nice if we could expect even minimal statistic comprehension from those making follow-on claims using the paper as supporting evidence.
No, your snark fails because you picked the wrong variables. Got Diabetes necessarily implies a population of Did Not Get Diabetes, so the r^2 would not be 1.0.
On the other hand, the r^2 between Have Diabetes and Water Exposure would be 1.0.
