Inflation and Relative Price Variability: Parks' Study Reexamined

The authors show that Richard W. Parks' (1978) widely cited evidence on the correlation between the rate of inflation and the variability of relative prices in the United States during 1948-75 depends on one observation, 1974. When the sample period is extended through 1989, the correlation depends on the observations for 1974 and 1980. Since both are years of large oil price shocks, the authors make the case that causation is likely to run from these shocks to relative price variability and inflation with accommodating monetary policy playing a role.