In Chapter 4, Built-in Data Structures – list, set, dict, specifically the Using set methods and operators recipe, we looked at a statistical process called the Coupon Collector's Test. The concept is that each time we perform some process, we save a coupon that describes some aspect or parameter for the process. The question is, how many times do I have to perform the process before I collect a complete set of coupons?
If we have customers assigned to different demographic groups based on their purchasing habits, we might ask how many online sales we have to make before we've seen someone from each of the groups. If the groups are all about the same size, it's trivial to predict the average number of customers we encounter ...