The Shady Merchants Who Have Been Gaming Amazon's Review System for Years

This article is from Full Stack Economics, a newsletter about the economy, technology, and public policy. My wife wants a can opener for Christmas, so I went on Amazon to find one. I typed "can opener" in the search box and sorted the list by the average customer review. My plan was to get the old-fashioned hand-crank kind. But the first page of results had a bunch of electric can openers with excellent reviews and reasonable prices.