Naturally, I wondered about the correlation between the two. After all, if the people making the most noise about college are correct, there should be a distinct positive correlation. Right?
I did a quick regression analysis on the data. The first article listed median income for 2005 and 2007. The second included the percent of the population older than 25 that had at least a bachelor's degree. Since I don't know how current the data from the second article is, I did two analyses: one for 2007 and another for 2005.
Here's the data that Gnumeric (my favorite spreadsheet application) produced for me:
|County||% B.A.||2007 M.I.|
|County||% B.A.||2005 M.I.|
|Adjusted R Square||−0.07292089330524|
|Adjusted R Square||−0.24086047950145|
If you don't know and/or care much for statistics, the key value to look for is "R Square". The closer that number is to 1, the more perfectly correlated the data. The closer to 0, the less the numbers have to do with each other. For 2007 that number is about 0.14. For 2005 it is about 0.01. Even the 2007 number does not indicate any correlation.
I, a devout doubter of the return on investment of college, was surprised by this. No correlation at all? Amazing. I'll grant that such a small sample (n=6) doesn't mean much, but I found it interesting nonetheless.