– Where It All Begins and Ends
I have browsed and purchased multiple
times in amazon.com and have seen this section “Customer who bought this item has
also bought”. I always thought, it’s not a very complex piece and it’s
easy to find out what the other person has purchased and display it in this
section. In one of the products, we are implementing this functionality and I was
searching in web for reference and landed in this page.
It is not as simple as I thought. It
uses a technique called collaborative filtering and there is a more specific
technique to implement this (Item based collaborative filtering).
Item-based collaborative is just one
form of collaborative filtering. Other alternatives
include user-based collaborative filtering where relationships between users
are of interest, instead. However, item-based collaborative filtering is
especially scalable with respect to the number of users.
Link to the sample source code (T-SQL,
C#) is also available.
Technical Debt – Definition and Resources: From Brad Appleton’s Blog.
Technical Debt [a.k.a. Design Debt] is the accumulated amount/cost of rework that will be necessary to correct and/or recover from the deviation between the current design of the system, versus that which is minimally complex yet sufficiently complete to ensure correctness & consistency for timely delivery. This effort grows more than linearly over time as a system becomes bigger and more complex.