Perhaps Amazon has had this feature for a while, but today, for the first time I noticed a section labeled “Customers Who Bought Related Items Also Bought” as seen in the screen shot above. I was looking at an unreleased book, which might explain why they couldn’t show me information based on customers who actually bought the item.
Has anyone else noticed this? Am I just late to the party? I tried to find more information online, but nothing showed up. I assume they are using some item similarity measure to assemble a set of related items, and then are basing collaborative filtering on the purchase history associated with that set.
I’m very curious to hear more from anyone who is familiar with this functionality.