2009/7/20 Liam Wyatt liamwyatt@gmail.com:
Rotating them would seem like a more viable solution than randomised - We don't want the situation where every new page in WP someone reads there is a new/different coloured donation button where last week there was none at all
- to go from nothing to that would be almost as bad as a flashing "donate
here, now!" banner.
Indeed, that's the reasoning behind the proposed approach. We don't want it to typically be changing constantly for an individual user. Yes, a sequential run does introduce various problematic biases.
An IP-address based hack could work, but would need to take into account dynamic IP addresses and such, without introducing strange new biases of its own. We'll discuss a bit further - good ideas / algorithms welcome. :-)