The Phillips Curve, an economic model developed by A. W. Phillips purports that inflation and unemployment have a stable and inverse relationship. This has been a fundamental guiding economic theory used by the Fed for decades to set interest rates. Various studies have proven the theory is bogus, yet proponents keep believing.
https://www.zerohedge.com/news/2019-01-15/yet-another-fed-study-concludes-phillips-curve-nonsense