And a serious one when perpetrated by the IMF´s Chief-Economist with colleagues who write: Oil Prices and the Global Economy: It’s Complicated:
Even though oil is a less important production input than it was three decades ago, that reasoning should work in reverse when oil prices fall, leading to lower production costs, more hiring, and reduced inflation. But this channel causes a problem when central banks cannot lower interest rates. Because the policy interest rate cannot fall further, the decline in inflation (actual and expected) owing to lower production costs raises the real rate of interest, compressing demand and very possibly stifling any increase in output and employment. Indeed, those aggregates may both actually fall. Something like this may be going on at the present time in some economies. Chart 3 is suggestive of a depressing effect of low expected oil prices on expected inflation: it shows the strong recent direct relationship between U.S. oil futures prices and a market-based measure of long-term inflation expectations.
…Our claim is simply that when an oil importer’s macroeconomic conditions warrant a very low central bank interest rate, a fall in oil prices could move the real interest rate in a way that runs counter to the positive income effect.
But the “causation” they allude to, from oil prices to expected inflation is just a figment of their collective imagination!
If they only looked at a longer time period (beginning in 2003 when the inflation expectation became available), they would have difficulty establishing even a simple correlation.
What you do notice in the chart above is that oil prices and inflation expectations fall in tandem when there is a negative demand shock. That´s very clear in 2008/09. More recently, since mid-2014, there the Fed has also tightened monetary policy – a negative demand shock. The tightening was initially expressed through Fed words and has been reflected in NGDP growth slipping, expected one year ahead FF rate rising, the dollar index rising (dollar appreciation) in addition to the oil price fall, among other indications of monetary policy tightening!