Traffic allocation not working
Hi! For some reason my allocated traffic does not split 50/50 between Original and Variation #1. It's been running for 11 days and we have 66% on the Original and 34% on the Variation #1. Anyone knows why it does not split evenly?
is it a new experiment or do have restarted ( and/or modified) an existing one? I hope, traffic is high enough, too?
Hi! It's a new project and it's been running for 11 days. It's only been 53 unique visitors to that site where I'm running the test, but still I think that 66% and 34% is somewhat uneven distribution of the traffic, wouldn't you say?
from my point of view, there are to less visitors. You can calculate the probability for this using Bernoulli-distribution but unless you have at least 100 visitors, i won't get nervous in any way.
Just to clarify how Optimizely allocates traffic:
When Optimizely buckets a visitor into an experiment that has a 50/50 traffic allocation, it "flips a coin" for each visitor. That is, each visitor has a 50% chance of being bucketed into one of the variations. Because of this, sometimes distributions will look a little lopsided when there's not a lot of traffic. Statistically, it should even out as you get more visitors
Thanks Daniel. But how about this: I currently have close to 100 visitors in 20 days on the page I am running the A/B test on. What happens if I change the traffic allocation to 90% on the variation (which has about 40% right now) to even it out?