Hedonic Price Indexes With Unobserved Product Characteristics, and Application to Personal Computers
- 1 January 2005
- journal article
- Published by Taylor & Francis Ltd in Journal of Business & Economic Statistics
- Vol. 23 (1), 61-75
- https://doi.org/10.1198/073500104000000262
Abstract
We show that hedonic price indexes may be biased when not all product characteristics are observed. We derive two primary sources of bias. The first source is a classical selection problem that arises due to changes over time in the values of unobserved characteristics. The second comes from changes in the implicit prices of unobserved characteristics. Next we show that the bias can be corrected for under fairly general assumptions using extensions of factor analysis methods. We test our methods empirically using a new comprehensive monthly dataset for desktop personal computer systems. For these data, we find that the standard hedonic index has a slight upward bias of approximately 1.4% per year. We also find that omitting an important characteristic (CPU benchmark) causes a large bias in the index with standard methods, but that this bias is essentially eliminated when the proposed correction is applied.Keywords
This publication has 8 references indexed in Scilit:
- A Reconsideration of Hedonic Price Indexes with an Application to PC’sAmerican Economic Review, 2003
- Inferring the rank of a matrixJournal of Econometrics, 1997
- Econometric estimates of price indexes for personal computers in the 1990'sJournal of Econometrics, 1995
- Automobile Prices in Market EquilibriumEconometrica, 1995
- Automobile Prices and Quality: Did the Gasoline Price Increases Change Consumer Tastes in the U.S.?Journal of Business & Economic Statistics, 1986
- Large Sample Properties of Generalized Method of Moments EstimatorsEconometrica, 1982
- Automobiles and Hedonic Quality MeasurementJournal of Political Economy, 1969
- The Problem of the True Index of the Cost of LivingEconometrica, 1939