As an avid reader and student of pairs trading, I wanted to share an awesome resource for advanced pairs trading and mean-reverting portfolios. Hudson and Thames released a 165-page ebook, for free, on the topic. It covers everything from co-integration, copulas, optimal trading rules, and machine learning for pairs selection, there are even lecture videos on youtube that go in more depth. The Definitive Guide to Pairs Trading. I'm super impressed and hope you all like it.