How accurate are Adsense channel figures?

[wanderingmind]

I have noticed that sometimes the channel numbers do not add up right. Say revenue in an ad channel is x, another ad channel is y, and the URL channel where both are displayed has its revenue z.

But when I add up the revenues of both the ad channels, x+y turns out to be larger than z! The channels are all just 48 hours old now. Is this normal?

If the figures do not add up, how am I going to test if my attempts at better adsense clicks and revenue are working or not?!

[incrediBILL]

The figures can be skewed because some of your income can actually come from ads being clicked in Google cache and I'm not sure if they connect your cached page name with your URL channels or not.

Worse yet, if someone has download and scraped one of your pages, and not taken off AdSense code (actually happened to me once) there can be clicks from that page recorded in your totals.

If you have a dynamic site, Google considers a new URL parameter to be a different page.

For instance:

example.com?page=1&q=color
example.com?page=1&q=size

The "q" parameter above is changing and therefore each instance is a new page.

Additionally, bad crawlers can get your pages wrong and generate their own "new page" which can then get indexed in Google assuming it doesn't generate a 404 and you may see some oddities in tracking that too.

ASA, care to add some comments on this one?