incrediBILL - 9:24 am on Oct 30, 2011 (gmt 0)
I've been watching it for years. It's not a one time occurrence based on low quality traffic, it's standard operating procedure.
Maybe on your site, doesn't behave the same exact way on my sites.
Best I can tell there is no cut and dried blanket behavior that can be attributed to all AdSense sites, just some commonalities that tend to manifest in many clusters of similar sites.
It's obviously a combination of factors that make AdSense behave the way it does and each site has the ability to, at some level, manipulate those behaviors. I've manipulated them for years when I see certain trends start to emerge on my site by changing various page factors and testing the results.
By changing both the on page and off page factors that are part of the AdSense equation the payouts can be manipulated. One of the factors is the keyword that brings the surfer to the page. By simply adjusting the keywords your page targets in the search engine can get higher payouts. Doing some A/B testing of keywords on several similarly targeted pages can be used to determine the sweet spot and get the max revenue from AdSense.
It's very similar to testing ad performance in AdWords, not that different really.