Life Cycle Price Trends and Product Replacement: Implications for the Measurement of Inflation
研究发现超市产品价格随上市时间下降，这种生命周期效应在CPI中常被误归为质量差异，导致通胀被低估约每年0.30个百分点。
The paper explores the extent to which products follow systematic pricing patterns over their life cycle and the impact this has on the measurement of inflation. Using a large U . S . scanner data set on supermarket products and applying flexible regression methods, we find that on average prices decline as items age. This life cycle price change is often attributed to quality difference in the construction of CPI as items are replaced due to disappearance or during sample rotations. This introduces a systematic bias in the measurement of inflation. For our data we find that the life cycle bias leads to the underestimation of inflation by around 0.30 percentage points each year for the products examined.