Much of our shopping has switched to online — which meant small business owners like CJ Tennant had to adapt their brick-and-mortar businesses for online shoppers. The increase in e-commerce also means a boom in customer data collection. So what kind of data is collected, and how is it used? We speak with Anteneh Ayanso and Arunesh Mathur about e-commerce data mining, and what to watch out for when legitimate data collection crosses the ethical line. (This is a repeat of an episode that first aired in Jan. 2021, and has been updated to reflect that.)