Unemployment Hits a Low. Then Comes the Recession
https://www.bloomberg.com/news/articles/2018-05-11/no-the-u-s-economy-isn-t-overheating
Flattening Yield Curve - Cause for Concern?
https://www.nytimes.com/2018/05/11/business/bond-rates-recession.html
Noah Smith surveys recent research in the area of business cycle analysis: