Welcome to WebmasterWorld Guest from 22.214.171.124
My impressions, ctr, earnings, are all over the place...there's no discernable trend. If I make a change in the ad format, etc, there never seems to be a difference.
I have pages that will go a couple of days with no clicks, then 20, then none, then 1 then 2 then none for a couple days, then 70, then 10, etc....it's all over the place. How do you know if any changes you make actually increase earnings? Any guidelines would be greatly appreciated.
For whatever it is you want to measure, calculate a moving average and see how wide you have to make the window before the data begins to look more or less like a smooth curve. Don't be surprised if it's 30 days or more at your current levels.
You wouldn't be surprised if your results were varying widely if you were just sampling data between 2:05pm and 2:06pm. When your traffic is not large enough, sampling a 24-hour period (or even a 1-week period or longer) can produce the same effect. The solution is to sample over a larger period.
Studying a moving average is a cheap and dirty way to get a feel for how big a period you need to sample in order to test a change to any given statistic.