Selecting Users For A/B (Champion/Challenger) Testing
        Posted  
        
            by Gordon Guthrie
        on Stack Overflow
        
        See other posts from Stack Overflow
        
            or by Gordon Guthrie
        
        
        
        Published on 2010-02-22T13:15:28Z
        Indexed on 
            2010/04/19
            23:33 UTC
        
        
        Read the original article
        Hit count: 584
        
We have a framework that offers A/B split testing.
You have a 'champion' version of a page and you develop a 'challenger' version of it.
Then you run the website and allocate some of your users the champion and some the challenger and measure their different responses.
If the challenger is better than the champion at achieving your metrics then you dethrone the champion and develop a new challenger...
My question is what mechanisms should I consider to allocate the versions?
A number of options spring to mind:
- odd or even IP address (or sub-segments) 
****.****.****.123gets champion but.124gets challenger - cookie push - check for a champion/challenger cookie, if it doesn't exist randomly allocate the user to one and push the cookie
 
Best practice? suggestions? comments? experience?
© Stack Overflow or respective owner