hai guys please tell me about Google Ad Channels?? google_ad_client = "pub**************" google_ad_channel =""; it is blank in my account please tell me about google_ad_channel Thanks
If its blank I guess it means your impressions and clicks are not being watched by any of your channels.
Channels are an easy way to track impressions and clicks for a particular ad or page very precisely. Guess you should read the adsense's faq.
To get reporting by location of an ad, you can setup "channels" for tracking. For me, each ad has two channels (think of them as labels). I add one for the site name, and one for the specific site location (say, SiteX_top_728x90) Specific site location helps you figure out performance, and the sitewide label lets you add up all site revenue.