A/B Testing with Practice in Python (Part Two)

This is the second part of A/B testing notes, which contains the practical issues and alternatives of A/B testing. The fundamental introduction of A/B testing can be found in the first part of the notes:

A/B Testing with Practice in Python (Part One) 

这里主要说A/B test对于不同方案的变量数有严格的限制，A/B test必须是单变量，但是在现实中很难保证control和test之间只有一个变量的差别。