On Quality and Variety Bias in Aggregate Prices
构建一般均衡模型分析产品品种和质量如何影响加总价格偏差，发现该偏差呈顺周期性，品种贡献持久而质量贡献在中期转为逆周期，忽略两者会低估经济周期波动的真实幅度。
Abstract How do product variety and quality affect the aggregate price bias? We develop a general equilibrium model that accounts for the joint interaction of product quality and variety. Our findings show that the aggregate price bias is procyclical and the contribution of product variety is persistent whereas the contribution of product quality becomes countercyclical in the medium to long run. We show that accounting for product quality and variety has critical implications on the measure of cyclical fluctuations. Measurements of cyclical fluctuations derived using the consumption deflator, which abstracts from changes in product quality and variety, underestimate the variables' true volatility.