Durable goods, price indexes and quality change: an application to automobile prices in Italy, 1988-1998.

The paper analyzes the problems of measurement of durable consumer prices posed by quality change. Theoretical price indexes are defined and used to analyze several empirical methods of estimation of quality adjusted price indexes. The paper shows that hedonic regressions and other quality adjustment methods commonly used by statistical agencies do not always provide reliable price estimators. The analysis suggests that the application of methods of measurement based on chain indexes may remove the measurement problems associated with quality change. The paper includes an application of the theory to the analysis of automobile prices in Italy during the period 1988-1998.