Standard theories of price adjustment are based on the problem of a single-product firm, and therefore they may not be well suited to analyze price dynamics in the economy with multiproduct firms. To guide new theory, we study a unique dataset with comprehensive coverage of daily prices in large...

We propose a simple, model-free way to measure price selection and its impact on inflation. Price selection exists when prices that change in response to aggregate shocks are not representative of the overall population of prices. Due to selection, increases (decreases) in inflation can be...