I‘m a big fan of data-driven website like fivethirtyeight.com. But sometimes the data doesn’t seem to back up the analysis.

Example: a blog post by Ben Casselman headlined “Americans don’t miss manufacturing — they miss unions.” “There are substantial variations” in average manufacturing wages, Casselman writes. The proof? “The average manufacturing production worker in Michigan earns $20.80 an hour, vs. $18.86 in South Carolina, according to data from the Bureau of Labor Statistics.”