One article I've found helpful with A/B testing is [1] which also describes some common statistical problems (e.g. Simpson's paradox as it applies to A/B testin

One article I've found helpful with A/B testing is [1] which also describes some common statistical problems (e.g. Simpson's paradox as it applies to A/B testing) based on case studies. It's written as a research paper by some folks at Microsoft, but it's definitely very readable. [1]: http://www.exp-platform.com/Documents/2009-ExPpitfalls.pdf http://www.exp-platform.com/Documents/2009-ExPpitfalls.pdf