Does Quality Adjustment Matter for Technologically Stable Products? An Application to the CPI for Food
研究了消费价格指数中匹配模型假设对技术稳定产品是否成立，发现样本替换时质量差异大可能导致低估价格变化和高估质量变化。
Most indexes in the Consumer Price Index (CPI) use a form of the “matched-model” approach. It is frequently assumed that this approach accurately reflects inflation for items that have no major trend in quality. In this paper we investigate that hypothesis using CPI data for retail food items. We find that CPI analysts may be correct on average when they decide that new and replacement items are similar in quality. We also find, however, that when sample items are replaced by items of significantly different quality the CPI imputation procedures may underestimate price change and overstate quality change.