To drop or add: Market timing and supermarket decisions on irradiated ground beef

This article investigates the sequential nature of supermarkets' decisions regarding irradiated ground beef using data collected from two separate supermarket surveys. We identify four mutually exclusive groups of supermarkets: those that adopted irradiated ground beef early and subsequently either continued or ceased offering the product-Early Adopters or Droppers, and those that at first chose not to adopt and subsequently either added or continued not offering the product-Adders or Never Adopters. We find that one set of store-level factors plays an important role in separating Early Adopters from Droppers, while a separate set of factors is important in separating Adders from Never Adopters.