I have been laid up this winter and have been working from home the past several months. Idle hands ARE the devil's work so I decided to take on a machine learning challenge at CodeProject.com and build a recommendation engine like Amazon, Facebook etc. These are interesting pieces of software that in commercial sites can work in conjunction with search engines to lead customers to content, products or items they might never would have looked at otherwise. In fact, this is something that might be useful on LMR - maybe have a recommendations window for when a user logs in? This way, older content that is on the site gets recycled and reviewed instead of disappearing into bit heaven.
I am posting this here since I think in robotics, the concepts of how to identify similar things would be useful for a robot. The article goes through the formulas and approach I took to the problem. I wrote the code in C#, but this could easily be converted to run as a service in the cloud, or could be a background process that runs a few times a day (more likely- this almost dims the lights when it starts running...) The point is that this gives a framework and an approach on how to address what is a pretty easy thing for you and me but is hard for a computer. There are also other examples written in JavaScript, Python and Java.
https://www.codeproject.com/Articles/1233227/Recommendation-Engine
I hope someone finds this interesting and useful.