|
C. Lanier Benkard, Patrick Bajari
NBER Working Paper No. 9980*
Issued in September 2003
NBER Program(s): IO
PR
---- 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 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 data set for desktop personal computer systems. For this 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.
*Published: Benkard, C. Lenair and Patrick Bajari. "Hedonic Price Indexes With Unobserved Product Characteristics," Journal of Business and Economic Statistics, 2005, v23(1,Jan), 61-75.
Would you like an annual subscription to NBER Working Papers? Click
here for more information.
You may purchase this paper on-line in .pdf format
from SSRN.com ($5) for electronic delivery.
Information for subscribers and others expecting no-cost downloads
Machine-readable bibliographic record -
MARC,
RIS,
BibTeX
| 
