Bayes’ Rule and App Search by Paul Christiano.
From the post:
In order to provide relevant search results, Quixey needs to integrate many different sources of evidence — not only each app’s name and description, but content from all over the web that refers to specific apps. Aggregating huge quantities of information into a single judgment is a notoriously difficult problem, and modern machine learning offers many approaches.
When you need to incorporate just a few pieces of information, there’s a mathematical version of “brute force” that works quite well, based on Bayes’ Rule:
Very smooth explanation of Bayes’ Rule if you need to get your feet wet!