The Little Handbook of Statistical Practice: http://www.tufts.edu/~gdallal/LHSP.HTM http://www.tufts.edu/~gdallal/LHSP.HTM It's the best stats resource I've co

The Little Handbook of Statistical Practice: http://www.tufts.edu/~gdallal/LHSP.HTM http://www.tufts.edu/~gdallal/LHSP.HTM It's the best stats resource I've come across, particularly for the stats behind split testing and multivariate testing. I've used it as a reference while building an A/B testing system in the past. For considerations in building a system to perform split testing and using such a system, the folks working on Microsoft's Experimentation Platform published an incredibly helpful paper: http://exp-platform.com/hippo.aspx http://exp-platform.com/hippo.aspx