Google Web Optimizer -- How long until winning combination?

I've had an A/B Test running in Google Web Optimizer for six weeks now, and there's still no end in sight. Google is still saying: "We have not gathered enough data yet to show any significant results. When we collect more data we should be able to show you a winning combination."

Is there any way of telling how close Google is to making up its mind? (开发者_运维知识库Does anyone know what algorithm does it use to decide if there's been any "high confidence winners"?)

According to the Google help documentation:

Sometimes we simply need more data to be able to reach a level of high confidence. A tested combination typically needs around 200 conversions for us to judge its performance with certainty.

But all of our conversions have over 200 conversations at the moment:

230 / 4061 (Original)

223 / 3937 (Variation 1)

205 / 3984 (Variation 2)

205 / 4007 (Variation 3)

How much longer is it going to have to run??

Thanks for any help.

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Is there any way of telling how close Google is to making up its mind?

You can use the GWO calculator to help determine how long a test will take based on a number of assumptions that you provide. Keep in mind though that it is possible that there is not significant difference between your test combination, in which case a test to see which is best would take an infinite amount of time, because it is not possible to find a winner.

(Does anyone know what algorithm does it use to decide if there's been any "high confidence winners"?)

That is a mystery, but with most, if not all, statistical tests, there is what's called a p-value which is the probability of obtaining a result as extreme as the one observed by chance alone. GWO tests run until the p-value passes some threshold, probably 5%. To be more clear, GWO tests run until a combination is significantly better than the original combination, such that the result only has a 5% chance of occurring by chance alone.

For your test there appears to be no significant winner, it's a tie.