Is the Fisher Effect for Real? A Reexamination of the Relationship Between Inflation and Interest Rates

The basic puzzle about the so-called Fisher effect, in which movements in short-term interest rates primarily reflect fluctuations in expected inflation, is why a strong Fisher effect occurs only for certain periods but not for others. This paper resolves this puzzle by reexamining the relationship between inflation and interest rates with modern time-series techniques. Recognition that the level of inflation and interest rates may contain stochastic trends suggests that the apparent ability of short-term interest rates to forecast inflation in the postwar United States is spurious. Additional evidence does not support the presence of a short-run Fisher effect but does support the existence of a long-run Fisher effect in which inflation and interest rates trend together in the long run when they exhibit trends.